Co-reporter:Wan-Zhen Qiao, Hang Xu, Peng Cheng, and Bin Zhao
Crystal Growth & Design June 7, 2017 Volume 17(Issue 6) pp:3128-3128
Publication Date(Web):April 17, 2017
DOI:10.1021/acs.cgd.7b00063
Two novel three-dimensional 3d-4f heterometallic-organic frameworks {[TbZn(BPDC)2(μ2-H2O)Cl(H2O)3]·5H2O·0.5DMA}n (1) and {[TbCo(BPDC)2(μ2-H2O)Cl(H2O)3]·8H2O·0.5DMA}n (2) have been synthesized and structurally characterized. They are isostructural and exhibit irregular one-dimensional channels with a large potential pore volume. Importantly, both of them demonstrate excellent catalytic activity for the chemical fixation of CO2 into cyclic carbonates under mild conditions. Moreover, the catalytic recycling of compound 1 as a representative example was explored; it can be easily separated and reused for at least four times without significant reduction in catalytic ability.
Co-reporter:Jie Dong, Hang Xu, Sheng-Li Hou, Zhi-Lei Wu, and Bin Zhao
Inorganic Chemistry June 5, 2017 Volume 56(Issue 11) pp:6244-6244
Publication Date(Web):May 8, 2017
DOI:10.1021/acs.inorgchem.7b00323
Two multifunctional metal–organic frameworks based on cubane-like tetrahedron Tb4 clusters as nodes have been synthesized and characterized. Compound 1 exhibits a 2D lanthanide–organic framework with Tb4 clusters as nodes, and compound 2 possesses a 3D framework with Tb4 clusters and Mn2+ as nodes. Interestingly, luminescent investigations on them reveal that the two compounds can act as recyclable luminescent probes for chromium(VI) anion species and the corresponding detection limit can reach 10–7 mol/L. Furthermore, 1 and 2 own efficient catalytic activity for the chemical fixation of CO2 with epoxides under mild conditions. Importantly, they both can be recycled at least three times without compromising the activity.
Co-reporter:Tian-Qun Song;Jie Dong;Hong-Ling Gao;Jian-Zhong Cui
Dalton Transactions 2017 vol. 46(Issue 40) pp:13862-13868
Publication Date(Web):2017/10/17
DOI:10.1039/C7DT02819A
A novel zinc-organic framework, {[Zn3(tza)2(μ2-OH)2(H2O)2]·H2O}n (1) (H2tza = 1H-tetrazolate-5-acetic acid), was synthesized through an in situ generated tetrazole ligand under hydrothermal conditions. In compound 1, tza2− ligands and Zn2+ are interlinked to form 2D layers, which are further pillared through μ2-OH groups to generate a 3D framework. Thermogravimetric analysis and powder X-ray diffraction confirm that 1 has high thermal stability, pH stability and solvent stability. Catalytic studies show that 1 exhibits excellent catalytic ability for the cycloaddition of CO2 with epoxides under 50 °C and 0.1 MPa. Importantly, 1 can be reused at least six times. Furthermore, luminescence investigations indicate that 1 can serve as a recyclable luminescence sensor to efficiently detect Cr2O72−/CrO42−, and the detection limit can reach 10−6 mol L−1 and 4 × 10−6 mol L−1, respectively.
Co-reporter:Bin Zhai;Hang Xu;Zhong-Yi Li;Chun-Shuai Cao
Science China Chemistry 2017 Volume 60( Issue 10) pp:1328-1333
Publication Date(Web):18 September 2017
DOI:10.1007/s11426-017-9103-3
A new 2D Eu-BTB framework (1) with stratified gridding structure of about 14.6 Å×16.9 Å was synthesized and characterized. Compound 1 displays excellent water stability with the pH 2–12. The luminescent investigations suggest that 1 could represent a chemical sensor of PO43- with high sensitivity and selectivity. Importantly, 1 as a sensor of PO43- can be reused at least five times. On the other hand, the catalytic investigations of 1 were carried out, indicating that 1 could be demonstrated as a recyclable catalyst for CO2 conversion with epoxides.
Co-reporter:Gang Xiong;Bing Yu;Jie Dong;Ying Shi;Liang-Nian He
Chemical Communications 2017 vol. 53(Issue 44) pp:6013-6016
Publication Date(Web):2017/05/30
DOI:10.1039/C7CC01136A
Investigations on metal–organic frameworks (MOFs) as direct catalysts have been well documented, but direct catalysis of the chemical conversion of terminal alkynes and CO2 as chemical feedstock by MOFs into valuable chemical products has never been reported. We report here two cluster-based MOFs I and II assembled from a multinuclear Gd-cluster and Cu-cluster, displaying high thermal and solvent stabilities. I and II as heterogeneous catalysts possess active catalytic centers [Cu12I12] and [Cu3I2], respectively, exhibiting excellent catalytic performance in the carboxylation reactions of CO2 with 14 kinds of terminal alkynes under 1 atm and mild conditions. For the first time catalysis of the carboxylation reaction of terminal alkynes with CO2 by MOF materials without any cocatalyst/additive is reported. This work not only reduces greenhouse gas emission but also provides highly valuable materials, opening a wide space in seeking recoverable catalysts to accelerate the chemical conversion of CO2.
Co-reporter:Hang Xu, Bin Zhai, Chun-Shuai Cao, and Bin Zhao
Inorganic Chemistry 2016 Volume 55(Issue 19) pp:9671-9676
Publication Date(Web):September 22, 2016
DOI:10.1021/acs.inorgchem.6b01407
A novel three-dimensional lanthanide–organic framework {[Eu(BTB)(phen)]·4.5DMF·2H2O}n (1) has been synthesized. Structural characterization suggests that framework 1 possesses one-dimensional channels with potential pore volume, and the large channels in the framework can capture CO2. Interestingly, investigations on the cycloaddition reaction of CO2 and epoxides reveal that compound 1 can be considered as an efficient catalyst for CO2 fixation with epoxides under 1 atm pressure. Importantly, 1 can be reused at least five times without any obvious loss in catalytic activity. Furthermore, the luminescent explorations of 1 reveal that 1 can act as a recyclable sensor of Al3+, and the corresponding detection limit can reach 5 × 10–8 M (1.35 ppb), which is obviously lower than the United States Environmental Protection Agency’s recommended level of Al3+ in drinking water (200 ppb). These results show that 1 has a level of sensitivity higher than that of other reported MOF-based sensors of Al3+.
Co-reporter:Hang Xu, Ming Fang, Chun-Shuai Cao, Wan-Zhen Qiao, and Bin Zhao
Inorganic Chemistry 2016 Volume 55(Issue 10) pp:4790
Publication Date(Web):May 2, 2016
DOI:10.1021/acs.inorgchem.6b00190
Three isostructural Ln-BTB frameworks (Ln = Eu (1), Dy (2), Yb (3)) were synthesized and structurally characterized, in which mononuclear and trinuclear [Ln3] units as nodes construct unprecedented (3,4,10)-connected 3D frameworks with (4·6·8)4(4·82)2(4·85)(62·84)(45·68·826·106) point symbol. The luminescent investigations revealed that compound 1 can sensitively and selectively detect Al3+, but comparably compound 2 could not detect Al3+ among various cations. More importantly, 1 as an Al3+ sensor can be reused at least five times, which represents the first recyclable metal organic framework (MOF)-supported Al3+ sensor. Additionally, magnetic investigations on 2 also were carried out, showing a single-molecule-magnet behavior.
Co-reporter:Zhi Chen, Ming Fang, Xiao-Min Kang, Yin-Ling Hou and Bin Zhao
Dalton Transactions 2016 vol. 45(Issue 1) pp:85-88
Publication Date(Web):13 Nov 2015
DOI:10.1039/C5DT02444G
A dinuclear Dy(III) compound (1) was structurally and magnetically characterized, displaying a single-molecule magnet (SMM) behavior with a relaxation energy barrier of 21(1) K. Interestingly, by only adding a suitable substituent on the ligand in 1, 1 as an SMM building unit, can be further assembled into a two-dimensional (2D) framework (2), which possesses a typical SMM behavior and a high relaxation energy barrier of 68(2) K. The result implied that the assembly of an SMM can effectively tune the energy barrier. To our knowledge, a cluster-based SMM assembled into a new 2D framework with SMM behavior is seldom reported.
Co-reporter:Chun-Shuai Cao, Huan-Cheng Hu, Hang Xu, Wan-Zhen Qiao and Bin Zhao
CrystEngComm 2016 vol. 18(Issue 23) pp:4445-4451
Publication Date(Web):21 Apr 2016
DOI:10.1039/C5CE02568K
Two unique 2D Zn-MOFs with the formulas {[Zn(btz)]n} (1) and {[Zn2(ttz)H2O]n} (2) were synthesized using in situ generated ligands under hydro(solvo)thermal conditions. Both 1 and 2 exhibit high thermo-stability, solvent-stability and pH-stability. Thermogravimetric analyses (TGA) reveal that 1 and 2 remain intact until about 365 °C and 332 °C, respectively. The samples of 1 and 2 were immersed in twelve common solvents for 24 hours, and the obtained PXRD patterns remain well consistent with the simulated ones. They were immersed in a series of solutions with pH values ranging from 1.0 to 14.0 for five hours, and the PXRD patterns of these samples remain unchanged spanning the pH range of 1–13. The luminescence investigations reveal that the compounds 1 and 2 can efficiently and selectively detect Cr2O72− or CrO42− among twenty-one anions. Importantly, they can be regenerated by a fast and simple method in detecting Cr2O72− or CrO42−.
Co-reporter:Wen-Min Wang, Wan-Zhen Qiao, Hong-Xia Zhang, Shi-Yu Wang, Yao-Yao Nie, Hong-Man Chen, Zhen Liu, Hong-Ling Gao, Jian-Zhong Cui and Bin Zhao
Dalton Transactions 2016 vol. 45(Issue 19) pp:8182-8191
Publication Date(Web):04 Apr 2016
DOI:10.1039/C6DT00220J
Nine dinuclear Ln(III) complexes, [Ln(dbm)2(L)]2 (Ln = Eu (1), Tb (2), Dy (3), Ho (4), Er (5)) and [Ln(dbm)2(L′)]2 (Ln = Tb (6), Dy (7), Ho (8), Er (9)) (dbm = 1,3-diphenyl-1,3-propanedione, HL = 2-[[(4-methoxy-phenyl)imino]methyl]-8-hydroxy-quinoline and HL′ = 2-[[(4-ethoxyphenyl)imino]methyl]-8-hydroxyquinoline) have been synthesized, and structurally and magnetically characterized. The nine complexes are all phenoxo-O bridged binuclear complexes, in which Ln1 and Ln1a are in an eight-coordinated environment bridged by two phenoxido oxygen atoms of two 8-hydroxyquinoline Schiff base ligands. Although complexes 3 and 7 have very similar structures, magnetic studies reveal that they exhibit different magnetic relaxation behaviors with the effective barriers (ΔE/kB) of 34.5 K for 3 and 67.6 K for 7. The dissimilar dynamic magnetic behaviors of 3 and 7 mostly result from the different electron-donating effect induced by the two alkoxy (–OCH3 and –OC2H5) of the 8-hydroxyquinoline Schiff base ligands. Meanwhile, for complexes 2, 5, 6 and 9, there are no observed magnetic relaxation behaviors under a zero dc field. In addition, the luminescence properties of 1, 2 and 6 were studied.
Co-reporter:Zhi-Lei Wu;Chang-Hong Wang;Dr. Bin Zhao;Jie Dong;Dr. Feng Lu;Dr. Wei-Hua Wang;Dr. Wei-Chao Wang;Dr. Guang-Jun Wu;Dr. Jian-Zhong Cui;Dr. Peng Cheng
Angewandte Chemie 2016 Volume 128( Issue 16) pp:5022-5026
Publication Date(Web):
DOI:10.1002/ange.201508325
Abstract
Based on the newly designed ligand 4′-(3,5-dicarboxyphenyl)-4,2′:6′,4′′-terpyridine (DCTP), a unique semi-conductive 3D framework {[CuΙCuΙΙ2(DCTP)2]NO3⋅1.5 DMF}n (1) with a narrow band gap of 2.1 eV, was obtained and structurally characterized. DFT calculations with van de Waals correction employed to explore the electronic structure of 1, clearly revealed its semi-conductive behavior. Furthermore, we found that 1 exhibits a superior band alignment with water to produce hydrogen and degrade organic pollutants. Without adding any photosensitizers, 1 displays an efficiently photocatalytic hydrogen production in water based on the photo-generated electrons under UV/Vis light. 1 also exhibits excellent photo-degradation of methyl blue under visible-light owing to the strong oxidization of excited holes. It is the first example of MOFs with doubly photocatalytic activities related to photo-generated electrons and holes, respectively.
Co-reporter:Zhi-Lei Wu;Chang-Hong Wang;Dr. Bin Zhao;Jie Dong;Dr. Feng Lu;Dr. Wei-Hua Wang;Dr. Wei-Chao Wang;Dr. Guang-Jun Wu;Dr. Jian-Zhong Cui;Dr. Peng Cheng
Angewandte Chemie 2016 Volume 128( Issue 16) pp:
Publication Date(Web):
DOI:10.1002/ange.201602323
Co-reporter:Zhi-Lei Wu;Chang-Hong Wang;Dr. Bin Zhao;Jie Dong;Dr. Feng Lu;Dr. Wei-Hua Wang;Dr. Wei-Chao Wang;Dr. Guang-Jun Wu;Dr. Jian-Zhong Cui;Dr. Peng Cheng
Angewandte Chemie International Edition 2016 Volume 55( Issue 16) pp:4938-4942
Publication Date(Web):
DOI:10.1002/anie.201508325
Abstract
Based on the newly designed ligand 4′-(3,5-dicarboxyphenyl)-4,2′:6′,4′′-terpyridine (DCTP), a unique semi-conductive 3D framework {[CuΙCuΙΙ2(DCTP)2]NO3⋅1.5 DMF}n (1) with a narrow band gap of 2.1 eV, was obtained and structurally characterized. DFT calculations with van de Waals correction employed to explore the electronic structure of 1, clearly revealed its semi-conductive behavior. Furthermore, we found that 1 exhibits a superior band alignment with water to produce hydrogen and degrade organic pollutants. Without adding any photosensitizers, 1 displays an efficiently photocatalytic hydrogen production in water based on the photo-generated electrons under UV/Vis light. 1 also exhibits excellent photo-degradation of methyl blue under visible-light owing to the strong oxidization of excited holes. It is the first example of MOFs with doubly photocatalytic activities related to photo-generated electrons and holes, respectively.
Co-reporter:Zhi-Lei Wu;Chang-Hong Wang;Dr. Bin Zhao;Jie Dong;Dr. Feng Lu;Dr. Wei-Hua Wang;Dr. Wei-Chao Wang;Dr. Guang-Jun Wu;Dr. Jian-Zhong Cui;Dr. Peng Cheng
Angewandte Chemie International Edition 2016 Volume 55( Issue 16) pp:
Publication Date(Web):
DOI:10.1002/anie.201602323
Co-reporter:Jie Dong; Ping Cui; Peng-Fei Shi; Peng Cheng
Journal of the American Chemical Society 2015 Volume 137(Issue 51) pp:15988-15991
Publication Date(Web):December 11, 2015
DOI:10.1021/jacs.5b10000
Zeolites, as one of the most important porous materials, are most widely utilized in sorbents, catalysis, and ion-exchange fields. However, the multi-functional lanthanide-zeolites constructed exclusively by lanthanide ions and oxygen linkers are to our knowledge unknown hitherto. Herein, we, for the first time, report the unique structure and multifunctions of lanthanide zeolites (1·Gd, 1·Tb, 1·Dy), featuring 60 nuclear [Ln60] nanocages as building blocks and ultrastrong alkali-resisting. These compounds possess extremely high stability and still retain single crystallinity after treatment in boiling water, 0.1 M HCl, and 20 M NaOH aqueous solutions. Magnetic studies revealed 1·Gd has large magnetocaloric effect with −ΔSmmax = 66.5 J kg–1 K–1, falling among the largest values known to date. Importantly, these lanthanide-zeolites themselves can efficiently catalyze the cycloaddition of CO2 with epoxides under mild conditions. Our finding extends the conventional zeolites to lanthanide counterparts, opening a new space for seeking novel and/or multifunctional zeolites.
Co-reporter:Huan-Cheng Hu, Chun-Shuai Cao, Yang Yang, Peng Cheng and Bin Zhao
Journal of Materials Chemistry A 2015 vol. 3(Issue 14) pp:3494-3499
Publication Date(Web):20 Feb 2015
DOI:10.1039/C4TC02958E
A novel triangular [Mn3] cluster-based 3D ferrimagnet [Na2Mn3(SO4)3(μ3-OH)2(μ2-OH2)2]n (1) was structurally and magnetically characterized. It exhibited both long-range magnetic ordering (TC = 12.0 K) and spin glass behaviour around 10 K and a butterfly-shaped magnetic hysteresis loop was observed. A peak (14.4 J kg−1 K−1) in the −ΔSmvs. temperature curve was obtained at 13.5 K. It is rather rare that the magnetocaloric effect of a ferrimagnet was explored and that the peak in the −ΔSmvs. temperature curve occurs above 10 K.
Co-reporter:Huan-Cheng Hu, Xiao-Min Kang, Chun-Shuai Cao, Peng Cheng and Bin Zhao
Chemical Communications 2015 vol. 51(Issue 54) pp:10850-10853
Publication Date(Web):01 Jun 2015
DOI:10.1039/C5CC03670D
A novel 3D tetrazole-bridged 3d–4f heterometallic MOF {(H3O)3[Gd3Mn2(Trz)4]·12H2O}n (1) with a hexanuclear [Gd6] cluster was obtained via in situ [2+3] cycloaddition reaction and structurally characterized, possessing good solvent and thermal stabilities, as well as a large magnetic entropy change −ΔSm = 40.3 J kg−1 K−1 for ΔH = 7 T at 2.0 K. To our knowledge, it is the first example of tetrazole-bridged 3d–4f heterometallic MOFs.
Co-reporter:Hang Xu, Chun-Shuai Cao and Bin Zhao
Chemical Communications 2015 vol. 51(Issue 51) pp:10280-10283
Publication Date(Web):21 Apr 2015
DOI:10.1039/C5CC02596F
A novel 3D Eu-BTB framework (1) containing three types of 1D channels was synthesized and structurally characterized. Compound 1 exhibits high thermostability and water stability with the pH range from 2 to 12. Additionally, the luminescence explorations revealed that 1 can sensitively and selectively detect pollutant PO43− among various colourless anions. More importantly, 1 represents the first example of regenerable MOF-based luminescent probes for detecting PO43−.
Co-reporter:Yin-Ling Hou, Hang Xu, Rui-Rui Cheng and Bin Zhao
Chemical Communications 2015 vol. 51(Issue 31) pp:6769-6772
Publication Date(Web):10 Mar 2015
DOI:10.1039/C5CC01181G
Two novel 3D frameworks were synthesized, and further nanosized to form nanospheres. Studies revealed that 2 is the first MOF-based luminescent sensor for detecting cyclohexane, and this is also the first time that quick regeneration, high sensitivity, high yield, and easy nanocrystallization of MOF-based luminescent sensors have been simultaneously realized.
Co-reporter:Peng-Fei Shi, Huan-Cheng Hu, Zhan-Yun Zhang, Gang Xiong and Bin Zhao
Chemical Communications 2015 vol. 51(Issue 19) pp:3985-3988
Publication Date(Web):08 Jan 2015
DOI:10.1039/C4CC09081K
Two cationic heterometal–organic frameworks (Eu-Zn (1·NO3−) and Tb-Zn (2·NO3−)) with NO3− counter-anions in the channels are structurally and luminously characterized. Both of them can serve as highly sensitive and highly selective luminescent probes for detecting I− ions in aqueous solutions. In particular, 2·NO3− can selectively and reversibly detect I− with a fast response time of just 10 s and an extremely low detection limit of 0.001 ppm. Mechanism studies reveal that I− is quickly oxidized to form I3− with the help of 1·NO3− or 2·NO3−, leading to luminescence quenching. This represents the first report of MOF-based luminescent probes for the detection of I− in aqueous solutions.
Co-reporter:Hang Xu, Huan-Cheng Hu, Chun-Shuai Cao, and Bin Zhao
Inorganic Chemistry 2015 Volume 54(Issue 10) pp:4585-4587
Publication Date(Web):May 7, 2015
DOI:10.1021/acs.inorgchem.5b00113
A unique three-dimensional Tb-BTB framework (1) with two types of one-dimensional channels was obtained and structurally characterized, exhibiting high thermal stability. Luminescent investigations reveal that 1 can detect Fe3+ with relatively high sensitivity and selectivity. Importantly, 1 as the luminescent probe of Fe3+ can be simply and quickly regenerated, which represents a rare example in reported luminescent sensors of Fe3+.
Co-reporter:Zhi-Lei Wu, Jie Dong, Wei-Yan Ni, Bo-Wen Zhang, Jian-Zhong Cui, and Bin Zhao
Inorganic Chemistry 2015 Volume 54(Issue 11) pp:5266-5272
Publication Date(Web):May 19, 2015
DOI:10.1021/acs.inorgchem.5b00240
One novel three-dimensional (3D) 3d–4f metal–organic framework (MOF), [TbZn(L)(CO3)2(H2O)]n (1) [HL = 4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine], has been successfully synthesized and structurally characterized. Structural analysis shows that compound 1 features a unique chiral interpenetrating 3D framework for the first time. The resulting crystals of 1 are composed of enantiomers 1a (P41) and 1b (P43), as was clearly confirmed by the crystal structure and the corresponding circular dichroism (CD) analyses of eight randomly selected crystals. The investigations on CD spectra based on every single crystal clearly assigned the Cotton effect signals. The powder X-ray diffraction measurement of 1 after being immersed in common solvents reveals that 1 possess excellent solvent stability. Furthermore, luminescent studies imply that 1 displays highly selective luminescent sensing of aldehydes, such as formol, acetaldehyde, and propanal.
Co-reporter:Wen-Min Wang; Hong-Xia Zhang; Shi-Yu Wang; Hai-Yun Shen; Hong-Ling Gao; Jian-Zhong Cui
Inorganic Chemistry 2015 Volume 54(Issue 22) pp:10610-10622
Publication Date(Web):October 30, 2015
DOI:10.1021/acs.inorgchem.5b01404
New dinuclear lanthanide(III) complexes based on an 8-hydroxyquinoline Schiff base derivative and β-diketonate ligands, [Ln2(hfac)4(L)2] (Ln(III) = Gd (1), Tb (2), Dy (3), Ho (4), Er (5)), [Ln2(tfac)4(L)2] (Ln(III) = Gd (6), Tb (7), Dy (8), Ho (9)), and [Dy(bfac)4(L)2·C7H16] (10) (L = 2-[[(4-fluorophenyl)imino] methyl]-8-hydroxyquinoline, hfac = hexafluoroacetylacetonate, tfac = trifluoroacetylacetonate, and bfac = benzoyltrifluoroacetone), have been synthesized. The single-crystal X-ray diffraction data show that complexes 1–10 are phenoxo-O-bridged dinuclear complexes; each eight-coordinated center Ln(III) ion is in a slightly distorted dodecahedral geometry with two bidentate β-diketonate coligands and two μ2-O bridging 8-hydroxyquinoline Schiff base derivative ligands. The magnetic study reveals that 1 and 6 display cryogenic magnetic refrigeration properties, whereas complexes 3, 8, and 10 show different SMM behaviors with energy barriers of 6.77 K for 3, 19.83 K for 8, and 25.65 K for 10. Meanwhile, slow magnetic relaxation was observed in 7, while no out-of-phase alternating-current signals were found for 2. The different dynamic magnetic behaviors of two Tb2 complexes and the three Dy2 complexes mainly derive from the tiny crystal structure changes around the Ln(III) ions. It is also proved that the β-diketonate coligands can play an important role in modulating magnetic dynamics of the lanthanide 8-hydroxyquinoline Schiff base derivative system.
Co-reporter:Xiao-Qing Zhao, Xu-Hui Liu, Xiao-Min Kang and Bin Zhao
Dalton Transactions 2015 vol. 44(Issue 43) pp:18856-18863
Publication Date(Web):29 Sep 2015
DOI:10.1039/C5DT02280K
A family of heterometallic 4f–3d coordination polymers with the common formula [LnCo1.5(L)2(H2O)5]n (Ln = Pr(1), Eu(2), Gd(3), Tb(4), Dy(5), Ho(6), and Er(7), and H3L = 4-(carboxymethoxy)isophthalic acid) was obtained under solvothermal conditions with the effect of NaN3, which was involved in the reactions but not in the final structure. All of the compounds were isostructural, and had a two-dimensional wave-like structure based on centrosymmetric [LnO2Co]–Co–[LnO2Co] motifs. The results of the magnetic measurements displayed that ferromagnetic interactions occurred in the frameworks (3–7) containing “heavy” lanthanide ions (Gd, Tb, Dy, Ho, and Er), which should be ascribed to the coupling between the LnIII and CoII ions. Furthermore, compound 5, containing DyIII ions, displayed field-induced slow magnetic relaxation.
Co-reporter:Rui-Rui Cheng, Zhi-Lei Wu, Yin-Ling Hou, Jie Dong, Jian-Zhong Cui, Bin Zhao
Inorganic Chemistry Communications 2015 Volume 51() pp:95-98
Publication Date(Web):January 2015
DOI:10.1016/j.inoche.2014.11.017
•A novel bi-triazole ligand was prepared and characterized.•Three copper-based coordination polymers were structurally characterized.•These compounds exhibit different EPR signals.Three Cu(II) coordination polymers: [Cu(XL)(NO3)2]n (1), {[Cu(XL)(4,4′-bpy)(NO3)2]·CH3CN}n (1a) and {[Cu(XL)3](NO3)2·3.5H2O}n (2) have been synthesized mainly based on a novel bi-triazole ligand N,N′-bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxdiimide bi(1,2,4-triazole) (XL) and characterized by X-ray crystallography, EPR spectra, elemental analyses, FT-IR spectra and PXRD patterns. Structure analyses reveal that compounds 1 and 1a exhibit 1D chains, and compound 2 features a 2D cationic framework. Additionally, the Cu(II) ions with various coordination environment in compounds 1, 1a and 2 exhibit different EPR properties.Three Cu(II) coordination polymers have been synthesized mainly based on a novel bi-triazole ligand. In these compounds, the Cu(II) ions with various coordination environments exhibit different EPR properties.
Co-reporter:Huan-Cheng Hu;Han-Shi Hu;Dr. Bin Zhao;Ping Cui;Dr. Peng Cheng;Dr. Jun Li
Angewandte Chemie International Edition 2015 Volume 54( Issue 40) pp:11681-11685
Publication Date(Web):
DOI:10.1002/anie.201504758
Abstract
MOFs with both multicentered metal–metal bonds and low-oxidation-state (LOS) metal ions have been underexplored hitherto. Here we report the first cubic [MnI8] cluster-based MOF (1) with multicentered MnIMnI bonds and +1 oxidation state of manganese (MnI or Mn(I)), as is supported by single-crystal structure determination, XPS analyses, and quantum chemical studies. Compound 1 possesses the shortest MnIMnI bond of 2.372 Å. Theoretical studies with density functional theory (DFT) reveal extensive electron delocalization over the [MnI8] cube. The 48 electrons in the [MnI8] cube fully occupy half of the 3d-based and the lowest 4s-based bonding orbitals, with six electrons lying at the nonbonding 3d-orbitals. This bonding feature renders so-called cubic aromaticity. Magnetic properties measurements show that 1 is an antiferromagnet. This work is expected to inspire further investigation of cubic metal–metal bonding, MOF materials with LOS metals, and metalloaromatic theory.
Co-reporter:Huan-Cheng Hu;Han-Shi Hu;Dr. Bin Zhao;Ping Cui;Dr. Peng Cheng;Dr. Jun Li
Angewandte Chemie 2015 Volume 127( Issue 40) pp:11847-11851
Publication Date(Web):
DOI:10.1002/ange.201504758
Abstract
MOFs with both multicentered metal–metal bonds and low-oxidation-state (LOS) metal ions have been underexplored hitherto. Here we report the first cubic [MnI8] cluster-based MOF (1) with multicentered MnIMnI bonds and +1 oxidation state of manganese (MnI or Mn(I)), as is supported by single-crystal structure determination, XPS analyses, and quantum chemical studies. Compound 1 possesses the shortest MnIMnI bond of 2.372 Å. Theoretical studies with density functional theory (DFT) reveal extensive electron delocalization over the [MnI8] cube. The 48 electrons in the [MnI8] cube fully occupy half of the 3d-based and the lowest 4s-based bonding orbitals, with six electrons lying at the nonbonding 3d-orbitals. This bonding feature renders so-called cubic aromaticity. Magnetic properties measurements show that 1 is an antiferromagnet. This work is expected to inspire further investigation of cubic metal–metal bonding, MOF materials with LOS metals, and metalloaromatic theory.
Co-reporter:Gang Xiong, Xiang-Yang Qin, Peng-Fei Shi, Yin-Ling Hou, Jian-Zhong Cui and Bin Zhao
Chemical Communications 2014 vol. 50(Issue 32) pp:4255-4257
Publication Date(Web):28 Jan 2014
DOI:10.1039/C3CC49342C
Two unique heptanuclear clusters Ln@Zn6 (Ln = Dy (1), Er (2)) were structurally and magnetically characterized. Each Dy3+/Er3+ is located in a nona-coordinate D3h coordination environment, and is encapsulated in a diamagnetic Zn6 cage. Compound 1 exhibits single-ion magnetic behavior, and is the first example of a single-ion magnet (SIM) constructed through embedding one magnetic anisotropic metal ion into a diamagnetic cage.
Co-reporter:Ai-Hong Yang, Ji-Yong Zou, Wen-Min Wang, Xue-Ying Shi, Hong-Ling Gao, Jian-Zhong Cui, and Bin Zhao
Inorganic Chemistry 2014 Volume 53(Issue 14) pp:7092-7100
Publication Date(Web):June 30, 2014
DOI:10.1021/ic402803s
Two three-dimensional polymeric Tb(III) and Yb(III) frameworks, namely, {[Tb3(Hptc)(ptc)(pdc)(H2O)6]·2H2O}n (1) and {[Yb2(ptc)(ox)(H2O)5]·7H2O}n (2) (H4ptc = pyridine-2,3,5,6-tetracarboxylic acid, H2pdc = pyridine-3,5-dicarboxylic acid, ox = oxalate), have been synthesized by a hydrothermal method and characterized by infrared spectra, elemental analysis, powder X-ray diffraction, thermogravimetric analysis, and single-crystal X-ray diffraction. Framework 1 shows an interesting three-dimensional (8,8)-connected net with a Schläfli symbol of (33·418·55·62)2(36·414·57·6), while 2 exhibits an unusual (4,8)-connected sqc21 net with a Schläfli symbol of (32·42·52)(34·48·512·64). Luminescence studies of 1 reveal that the luminescence intensity increases when the framework is dehydrated.
Co-reporter:Gang Xiong, Hang Xu, Jian-Zhong Cui, Qing-Lun Wang and Bin Zhao
Dalton Transactions 2014 vol. 43(Issue 15) pp:5639-5642
Publication Date(Web):20 Jan 2014
DOI:10.1039/C3DT53251H
Triple core–shell structures in the Cu24Gd6 and Cu24Dy6 clusters were first observed and structurally characterized. The magnetic investigations reveal that Cu24Gd6 possesses the significant magnetic entropy change (−ΔSm) of 21.2 J kg−1 K−1 for ΔH = 7 T, and a slow magnetization relaxation is observed in Cu24Dy6.
Co-reporter:Yin-Ling Hou, Rui-Rui Cheng, Gang Xiong, Jian-Zhong Cui and Bin Zhao
Dalton Transactions 2014 vol. 43(Issue 4) pp:1814-1820
Publication Date(Web):15 Oct 2013
DOI:10.1039/C3DT52305E
Through hydrothermal reactions with corresponding lanthanide nitrates and 4-(4-carboxyphenylsulfonyloxy)-3-metnoxybenzoic acid (H2vspc), seven novel three-dimensional (3D) lanthanide–organic frameworks ([Ln(vspc)(Hvspc)(H2O)]n [Ln = Pr (1), Eu (2), Gd (3), Tb (4), Dy (5), Ho (6) and Er (7)]) have been synthesized and structurally characterized. All of them are isostructural and crystallize in the monoclinic crystal system, P21/c space group. Their structures feature a (3,6)-connected topological network, in which Ln3+ were connected by carboxylate groups to give a 1D lanthanide chain, and the adjacent chains are further spanned by vspc2− and Hvspc− anions to form a 3D framework. The luminescent properties and lifetimes of 2 (EuIII), 4 (TbIII), and 5 (DyIII) have been studied, and the corresponding luminescent lifetimes are 0.53, 0.99 and 0.014 ms, respectively. The magnetic investigations reveal that compound 3 displays weak antiferromagnet interaction, 4 and 5 exhibit ferromagnetic coupling, and compound 5 exhibits slow magnetic relaxation behavior.
Co-reporter:Zhi-Lei Wu, Jie Dong, Wei-Yan Ni, Bo-Wen Zhang, Jian-Zhong Cui and Bin Zhao
Dalton Transactions 2014 vol. 43(Issue 44) pp:16838-16845
Publication Date(Web):15 Sep 2014
DOI:10.1039/C4DT02427C
Two novel tetra- and deca-nuclear dysprosium compounds, namely, [Dy4(μ3-OH)2(L)10(bipy)2(H2O)2]n (1) and {[Dy10(μ3-OH)8(L)22(bipy)2(H2O)2]·5H2O}n (2) (L = 3-fluoro-4-(trifluoromethyl)benzoic acid; bipy = 2,2′-bipyridine), have been successfully obtained by hydrothermal reaction at different pH values. The solid state structures of 1 and 2 were established by the single crystal X-ray diffraction technique, and both of them exhibit complicated 1D chains with [Dy4] (1) and [Dy10] (2) cluster units, respectively. Adjacent [Dy4] in 1 and [Dy10] in 2 are connected by two bridging carboxylate groups in the η1:η1:μ2 mode. Magnetic studies reveal that they exhibit different magnetic relaxation behaviors with the energy barrier of 23.6 K for 1 and 3.2 K for 2. Interestingly, the large divergence in both the structures and magnetic properties for 1 and 2 only originated from the different pH values in preparing them.
Co-reporter:Li-Xian Chang, Gang Xiong, Li Wang, Peng Cheng and Bin Zhao
Chemical Communications 2013 vol. 49(Issue 11) pp:1055-1057
Publication Date(Web):29 Oct 2012
DOI:10.1039/C2CC35800J
Two 24-nuclear lanthanide clusters, Gd24 and Dy24 were obtained and structurally characterized. Magnetic investigations reveal that Gd24 exhibits the largest entropy change (−ΔSm) of 46.12 J kg−1 K−1 for ΔH = 7 T in all reported molecular clusters, and single-molecule magnet behaviour is observed in Dy24.
Co-reporter:Yin-Ling Hou, Gang Xiong, Peng-Fei Shi, Rui-Rui Cheng, Jian-Zhong Cui and Bin Zhao
Chemical Communications 2013 vol. 49(Issue 54) pp:6066-6068
Publication Date(Web):14 May 2013
DOI:10.1039/C3CC42545B
Two unique 3D coordination polymers based on octahedral [Ln6] (Ln = Gd (1), Dy (2)) clusters as nodes were synthesized, exhibiting a novel (3,12)-connected topology with the symbol of (420·626·820)(43)4. The magnetic studies reveal that 1 shows a −ΔSm = 46.6 J kg−1 K−1, falling among the largest values known to date, and 2 displays slow magnetic relaxation behavior. Both 1 and 2 have high thermal and solvent stabilities.
Co-reporter:Peng-Fei Shi, Gang Xiong, Bin Zhao, Zhan-Yun Zhang and Peng Cheng
Chemical Communications 2013 vol. 49(Issue 23) pp:2338-2340
Publication Date(Web):04 Feb 2013
DOI:10.1039/C3CC38402K
Two novel Dy–Cu MOFs were structurally and magnetically characterized. The results reveal that it is the first example of anion-induced change of structure interpenetration and magnetic properties in 3d–4f MOFs.
Co-reporter:Xiao-Qing Zhao, Xu-Hui Liu, Ji-Jing Li and Bin Zhao
CrystEngComm 2013 vol. 15(Issue 17) pp:3308-3317
Publication Date(Web):27 Nov 2012
DOI:10.1039/C2CE26695D
Ten novel lanthanide-based coordination polymers {[LnL(H2O)2]·H2O}n (Ln = Pr (1), Nd (2), Eu (3), Gd (4), Tb (5), Dy (6), Ho (7), Er (8), Yb (9), and Lu (10), H3L = 2-(carboxylmethoxy)terephthalic acid), have been successfully synthesized through hydrothermal reactions of corresponding Ln(OH)3 with semirigid tricarboxylate H3L ligands. Compounds 1 and 2 are isostructural, containing a 3D porous framework built of carboxylate-bridged layers with 66-topology, while 3–10 display the same 2D double-layer structure based on binuclear Ln2O2 units with 43·63-topology. The PXRD and TGA prove their phase purity and high thermal stability, respectively. Photoluminescent studies indicate the efficient energy transfer from L3− ligand to Ln3+ ions, exhibiting the typical intense emissions of corresponding Ln3+ ions in the visible region. The magnetic exchange interactions also are studied in compounds 4–7 for their short O bridges between Ln3+ ions, and the results show that there may be ferromagnetic interactions in 4–6, while in 7 the interactions cannot be distinctly deduced from the curves due to the nature of the Ho3+ ions. Furthermore, compound 6 displays slow magnetization relaxation, exhibiting single-molecule magnetic behavior.
Co-reporter:Xiao-Qing Zhao, Xu-Hui Liu and Bin Zhao
Dalton Transactions 2013 vol. 42(Issue 41) pp:14786-14793
Publication Date(Web):08 Aug 2013
DOI:10.1039/C3DT51769A
A series of lanthanide-based organic frameworks with formulas of {[PrL(H2O)2]·2H2O}n (1) and {[Ln3L3(H2O)2]·2H2O}n (Ln = Eu (2), Gd (3), Tb (4), Dy (5), Ho (6), Er (7); H3L = 4-(carboxymethoxy)isophthalic acid), were hydrothermally synthesized and structurally characterized. It is the first time that 4-(carboxymethoxy)isophthalic acid is employed in producing lanthanide compounds. The seven compounds exhibit two types of structures with the decreasing radius of the lanthanide ions, representing the lanthanide contraction effect. Compound 1 with the large Pr3+ ion displays a 2D layered structure with a binodal (4,4)-connected topology with the Schläfli symbol of (3363)2, whereas compounds 2–7 with small Ln3+ ions feature a 3D framework constructed from carboxyl groups with a (5,6,8)-connected topology with the Schläfli symbol of (324454)·(34445463)·(344856698). The luminescence and magnetic properties were investigated, and the results indicate that the H3L ligand can sensitize the lanthanide luminescence in compounds 2, 4 and 5 and makes a contribution to the antiferromagnetic interactions in compound 3 or the uncertain magnetic interactions in compounds 4–7. Additionally, the thermal analyses suggest the high thermal stability of compounds 1–7.
Co-reporter:Ming Fang, Hanhua Zhao, Andrey V. Prosvirin, Dawid Pinkowicz, Bin Zhao, Peng Cheng, Wolfgang Wernsdorfer, Euan K. Brechin and Kim R. Dunbar
Dalton Transactions 2013 vol. 42(Issue 41) pp:14693-14701
Publication Date(Web):01 Aug 2013
DOI:10.1039/C3DT51727F
A series of isostructural octanuclear lanthanide complexes of general formula [Ln8(sao)4(μ3-OH)4(NO3)12(DMF)12] (Ln = Nd (1), Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Ho (7), Er (8); DMF = dimethylformamide) have been prepared via reactions of salicylaldoxime (saoH2), tetramethylammonium hydroxide (Me4NOH) with the appropriate lanthanide nitrate salt (Ln(NO3)3·6H2O). The metallic skeletons of the complexes describe [Ln4] tetrahedra encapsulated inside a [Ln4] square with the inner core stabilised through μ3-OH− ions and the periphery by μ4-sao2− ligands. The magnetic properties of compounds 2–8 were investigated by dc and ac magnetometry. Temperature dependent ac magnetic susceptibility data reveal that the dysprosium analogue (6) displays an out-of-phase signal in the absence of an applied magnetic field indicative of slow relaxation of the magnetization typical of a Single-Molecule Magnet (SMM). Micro-SQUID measurements reveal temperature and sweep rate dependent hysteresis below 1.0 K.
Co-reporter:Ming Fang, Ji-Jing Li, Peng-Fei Shi, Bin Zhao and Peng Cheng
Dalton Transactions 2013 vol. 42(Issue 18) pp:6553-6563
Publication Date(Web):13 Feb 2013
DOI:10.1039/C3DT32861A
Eight three-dimensional lanthanide–organic frameworks: [Ln(BPDC)1.5(DMF)(H2O)2]·2H2O (Ln = Eu (1), Gd (2), Tb (3), Dy (4); BPDC = 4,4′-dicarboxylate-2,2′-dipyridine anion), [Ln(BPDC)(DMF)2(NO3)] (Ln = Eu (5), Gd (6), Tb (7), Dy (8)) were fabricated and structurally characterized. Compounds 1–4 are isostructural, belonging to the triclinic system with space group P, while compounds 6–8 belong to the monoclinic system with space group C2/c. Structural differences between two types of compounds may be caused by different reaction conditions. Magnetic properties of 2–4 and 6–8 have been investigated and only compounds 4 and 8 display significant frequency-dependence, albeit without reaching the characteristic maxima above 2 K, implying slow magnetic relaxation behaviors in 4 and 8. After the application of a DC field, good peak shapes of AC signal were obtained and got the energy barrier for 4, ΔE/kB = 79.80 K and the pre-exponential factor τ0 = 1.28 × 10−10 s, for 8, ΔE/kB = 38.15 K and τ0 = 2.47 × 10−9 s. Geometrical differences in the crystal fields of Dy3+ in 4 and 8 seem to be responsible for the large divergence of their magnetic behaviors. Luminescence analyses were performed on coordination polymers containing Eu3+, Tb3+, and Dy3+, which exhibit the characteristic transitions of corresponding lanthanide ions, and give the lifetime (τ0) of 1, 3, 4, 5, 7 and 8 are 0.56 ms, 0.89 ms, 8.48 μs, 0.60 ms, 0.75 ms and 36.35 μs, respectively.
Co-reporter:Yin-Ling Hou, Gang Xiong, Bo Shen, Bin Zhao, Zhi Chen and Jian-Zhong Cui
Dalton Transactions 2013 vol. 42(Issue 10) pp:3587-3596
Publication Date(Web):27 Nov 2012
DOI:10.1039/C2DT32390G
Six novel three-dimensional (3D) lanthanide metal–organic frameworks (LnMOFs), {[Ln2(ispc)3(H2O)3]·mH2O}n (Ln = Pr (1, m = 5); Eu (2, m = 5); Gd (3, m = 4); Tb (4, m = 5); Dy (5, m = 5) and Ho (6, m = 4)), ispc = 3-(4-carboxyphenylsulfonyloxy)-4-methoxybenzoic anion) have been synthesized under hydrothermal conditions. Single crystal X-ray diffraction revealed they are isostructural and crystallize in the triclinic crystal system, space group P. The investigations on luminescent properties and lifetimes of 2 (EuIII), 4 (TbIII), and 5 (DyIII) exhibit characteristic emissions of EuIII, TbIII and DyIII ions and the corresponding luminescent lifetimes are 0.14 ms, 9.93 μs and 1.25 ms, respectively. The different luminescent intensities and lifetimes among them were further discussed. Furthermore, magnetic studies of 1–6 reveal that 3–6 exhibit ferromagnetic coupling, and 5 (DyIII) exhibits remarkably slow magnetic relaxation behavior with the energy barrier ΔE/kB = 49.2 K.
Co-reporter:Bo Shen, Peng-Fei Shi, Yin-Ling Hou, Fan-Fan Wan, Dong-Liang Gao and Bin Zhao
Dalton Transactions 2013 vol. 42(Issue 10) pp:3455-3463
Publication Date(Web):27 Nov 2012
DOI:10.1039/C2DT32515B
Five novel compounds {[Cu(CMA)]·0.8H2O}n (1), {[Cu(CMA)(bpy)0.5]·0.5DMF}n (2), {[Cu(CMA)(bpy)(H2O)]·0.5H2O}n (3), {[Cu2(CMA)(DPA)(bpy)2(H2O)]ClO4}n (4) and {[Cu3(CMA)(DPA)(bpy)4(OH)](ClO4)2·3H2O)}n (5) (H2CMA = 3-(carboxymethoxy)-5-methylbenzoic acid, HDPA = 2-(3,5-dimethylphenoxy)acetic acid, bpy = 4,4′-bipyridine) were synthesized and characterized by single crystal X-ray diffraction. Interestingly, the kinds of ligands included in these compounds are different: 1 contains single-ligand CMA2−; 2 and 3 comprise two kinds of ligands (CMA2− and bpy); 4 and 5 cover three kinds of ligands (CMA2−, DPA− and bpy). Structural analyses reveal that 1–3, and 5 are three-dimensional (3D) frameworks, while 4 is a 2D layer. Noteworthily, 1 possesses two types of channels: six-star and hexagonal ones. 3 displays a three-fold interpenetrating 3D framework. The structural diversity of the compounds may have originated from different anions, solvents and temperatures. Variable-temperature magnetic susceptibility measurements were carried out on compounds 1, 2 and 4, and the magnetic properties are dramatically different due to the structural diversities. The magnetic data of 1 shows an antiferromagnetic interaction with J = −54.84 cm−1 estimated from the Bonner–Fisher model. The magnetic data of 2 was least-square fitted to the Blenaey–Bowers equation with J = −131.01 cm−1, indicating the existence of a strong antiferromagnetic interaction between two adjacent Cu2+. The magnetic data of linear tetranuclear structure 4 was best fitted to the expression derived from the Hamiltonian H = −2(2J1S1S2 + J2S1S1*). The best fitting parameters are J1 = −17.48 cm−1 and J2 = −65.26 cm−1, which also indicate an antiferromagnetic interaction. Simultaneously, the magneto-structural relationship was discussed.
Co-reporter:Gang Xiong, Yin-Ling Hou, Jian-Zhong Cui, Bin Zhao
Inorganic Chemistry Communications 2013 Volume 35() pp:89-91
Publication Date(Web):September 2013
DOI:10.1016/j.inoche.2013.05.030
•A new Fe8 cluster was synthesized and structurally characterized.•Magnetic susceptibility measurement indicates the antiferromagnetic coupling existing between adjacent FeIII centers with zero spin ground state.•Fe8 cluster exhibits an irreversible redox process.A new cluster [Fe8(μ4-O)3(teaH)3(tea)(IBA)6(H2O)3](NO3)3·3H2O (1) (teaH3 = triethylolamine, IBA = isobutyric acid) was synthesized and structurally characterized. The octanuclear cluster is constructed by three Fe4 tetrahedrons via sharing the edges. Magnetic susceptibility measurement indicates that the antiferromagnetic couplings exist between adjacent FeIII centers with zero spin ground state. Cyclic voltammogram exhibit an irreversible redox process.A new cluster [Fe8(μ4-O)3(teaH)3(tea)(IBA)6(H2O)3](NO3)3·3H2O (1) (teaH3 = triethylolamine, IBA = isobutyric acid) was synthesized and structurally characterized. Magnetic susceptibility indicates that the strong antiferromagnetic couplings exist between adjacent FeIII centers with zero spin ground state.
Co-reporter:Ping Cui ; Yu-Guang Ma ; Huan-Huan Li ; Bin Zhao ; Jian-Rong Li ; Peng Cheng ; Perla B. Balbuena ;Hong-Cai Zhou
Journal of the American Chemical Society 2012 Volume 134(Issue 46) pp:18892-18895
Publication Date(Web):October 31, 2012
DOI:10.1021/ja3063138
A zeolite-like microporous tetrazole-based metal–organic framework (MOF) with 24 nuclear zinc cages was synthesized and characterized. It exhibits high CO2 adsorption capacity up to 35.6 wt % (8.09 mmol/g) and excellent CO2/CH4 selectivity at 273 K/1 bar, being among the highest values known to date. Theoretical calculations based on simulated annealing techniques and periodic DFT revealed that CO2 is predominantly located around the inner surface of the cages through multipoint interactions, in particular, around the aromatic tetrazole rings. Importantly, it is the first time that multipoint interactions between CO2 molecules and frameworks resulting in high CO2 uptake are observed.
Co-reporter:Peng-Fei Shi, Bin Zhao, Gang Xiong, Yin-Ling Hou and Peng Cheng
Chemical Communications 2012 vol. 48(Issue 66) pp:8231-8233
Publication Date(Web):28 Jun 2012
DOI:10.1039/C2CC33707J
We present one 3D cationic MOF (1-ClO4), which exhibits high thermal stability and strong alkali resistance. More importantly, it displays fast, selective capture of, and acts as a luminescent probe for, pollutant CrO42− by anion exchange. Additionally, 1-ClO4 exhibits interesting slow magnetic relaxation behavior at low temperature.
Co-reporter:Ping Cui ; Lijun Ren ; Zhi Chen ; Huancheng Hu ; Bin Zhao ; Wei Shi ;Peng Cheng
Inorganic Chemistry 2012 Volume 51(Issue 4) pp:2303-2310
Publication Date(Web):January 30, 2012
DOI:10.1021/ic2023105
Four tetrazole-based three-dimensional (3D) metal–organic frameworks (MOFs), {[CuII(btz)]·0.5H2O}n (1), [CuII(btz)]n (1′), {[CuII(btz)]·0.5I2}n (1′·0.5I2), and [CuIICuI2(btz)2]n (2) [H2btz = 1,5-bis(5-tetrazolo)-3-oxapentane)], have been successfully obtained and characterized by crystallography. Compound 1 features a chiral porous framework. The bulk crystallization of 1 is composed of enantiomers 1a (P41) and 1b (P43), which has been demonstrated by the crystal structure analyses of nine crystals of 1 randomly selected. The Cotton effect displayed in the solid-state circular dichroism spectrum of 1 is therefore attributed to enantiomeric excess rather than enantiopurity. The completely dehydrated phase of 1, that is, 1′, can adsorb 0.5 I2 molecule per formula unit to yield compound 1′·0.5I2, which has been supported by single-crystal X-ray diffraction, elemental analysis, and thermogravimetric analysis. The locations of I2 in the pores were unambiguously determined, and the interactions between I2 molecules and the pore structures were investigated. Compound 2 crystallizes in an achiral C2/c space group. Interestingly, the formations of chiral 1 and achiral 2 significantly depend on the reaction temperature. Between 80 and 140 °C, we got compound 1 as the only product. At 150 °C, both 1 and 2 were in coexistence in the final product. From 160 to 180 °C, only compound 2 was obtained. More interestingly, treatment of the crystals of 1 or the mixture of 1 and 2 obtained at 150 °C in their mother liquor at 170 °C yielded the crystals of 2 in a single phase.
Co-reporter:Yue Liu, Zhi Chen, Jia Ren, Xiao-Qing Zhao, Peng Cheng, and Bin Zhao
Inorganic Chemistry 2012 Volume 51(Issue 14) pp:7433-7435
Publication Date(Web):June 26, 2012
DOI:10.1021/ic300372v
Two novel two-dimensional 3d–4f networks based on planar Co4Ln2 clusters supported by rigid 4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine afford the first examples of high-dimensional networks with 3d–4f clusters behaving as single-molecule magnets.
Co-reporter:Ya Zuo, Ming Fang, Gang Xiong, Peng-Fei Shi, Bin Zhao, Jian-Zhong Cui, and Peng Cheng
Crystal Growth & Design 2012 Volume 12(Issue 8) pp:3917-3926
Publication Date(Web):July 10, 2012
DOI:10.1021/cg300323u
Eight coordination polymers associated with the organic ligand 2,2′-bipyridyl-4,4′-dicarboxylic acid (abbreviated H2BPDC): {[Zn(BPDC)(H2O)3]·3H2O}n (1), [Zn(BPDC)(H2O)2]n (2), [Co(BPDC)(H2O)3]n (3), [Co(BPDC)(H2O)2]n (3a), [Cu(BPDC)(H2O)]n (4), {[Cu(BPDC)(H2O)2]·2H2O}n (4a), [Mn(BPDC)(H2O)2]n (5), and {[Mn(BPDC)]·2H2O}n (5a) were prepared by hydrothermal methods and structurally characterized. The structure analyses reveal that 1 exhibits a one-dimension chain, and 2, 3a, 5, and 5a are complicated 3D structures. 2 displays a 2-fold interpenetrating chiral 3D framework with the rare (12,3) topology and 5 is a chiral 3D framework. 4 and 4a are two-dimensional networks, and 3 is a chiral 1D chain. The structural contrasts between 1 and 2, 3 and 3a, 4 and 4a, and 5 and 5a display the transformations from low to high dimensional motif, and/or from achiral to chiral structures. Interestingly, the large structure divergences mainly originated from the different reaction temperature (It should be noted that 3a, 4a, and 5a were also obtained independently by us, although they had been reported. Herein, they were only used to discuss the structural comparison investigations). The luminescent properties of 1 and 2 have been explored and compared with that of the ligand. The Cotton effect in solid circular dichroism (CD) spectra of 2 was significantly observed, indicative of the chirality of 2. Magnetic properties analyses for 3 and 5 were performed.
Co-reporter:Peng-fei Shi, Zhi Chen, Gang Xiong, Bo Shen, Jing-Zhe Sun, Peng Cheng, and Bin Zhao
Crystal Growth & Design 2012 Volume 12(Issue 11) pp:5203-5210
Publication Date(Web):October 11, 2012
DOI:10.1021/cg300277m
Ten new 3D lanthanide-based compounds, {[Ln4(CPOA)6(H2O)4]·H2O}n (Ln = Eu (1), Gd (2), Tb (3), Dy (4), Ho (5)) and [Ln(CPOA)(C2O4)0.5(H2O)]n (Ln = Eu (1a), Gd (2a), Tb (3a), Dy (4a), Ho (5a)) (CPOA2– = 4-carbomethoxybenzoate), have been synthesized by a hydrothermal method under different temperatures. The compounds 1–5 were obtained at 140 °C. When the temperature went up to 180 °C, the ligands partly decomposed to C2O42–, then came into being compounds 1a–5a. The two series of compounds displayed the differences not only in structure but also in thermal stability and luminescent and magnetic properties. Compounds 1–5 crystallize in the triclinic system, space group P1̅, whereas compounds 1a–5a belong to the monoclinic system with space group P21/c. Thermal analyses were carried out on 1–5 and 1a–3a. Solid luminescence studies of compounds 1 and 1a, 3 and 3a, and 4 and 4a show the characteristic bands of Eu3+, Tb3+, and Dy3+, respectively. Magnetic properties were investigated on 2–4 and 2a–4a. The out-of-phase signals (χM″) of 4 exhibit a strong frequency dependence, suggesting the existence of slow magnetic relaxation behavior in 4.
Co-reporter:Zhi Chen, Dong-Liang Gao, Chun-Hua Diao, Yue Liu, Jia Ren, Ji Chen, Bin Zhao, Wei Shi, and Peng Cheng
Crystal Growth & Design 2012 Volume 12(Issue 3) pp:1201-1211
Publication Date(Web):January 31, 2012
DOI:10.1021/cg201197k
Nine compounds based on o-carboxylphenoxyacetate acid (H2OCPA) ligand: [Cu(OCPA)(4,4′-bipy)0.5]n (1), {[Cu2(OCPA)2(4,4′-bipy)2(H2O)]·H2O}n (2), [Co2(OCPA)2(4,4′-bipy)(H2O)4] (3), {[Co(OCPA)(4,4′-bipy)0.5(H2O)]·H2O}n (4), {[Co(OCPA)(4,4′-bipy)1.5]·0.5H2O}n (5), [Ni2(OCPA)2(4,4′-bipy)(H2O)4] (6), {[Ni(OCPA)(4,4′-bipy)1.5]·2H2O}n (7), {[Zn(OCPA)(4,4′-bipy)0.5(H2O)]·H2O}n (8), and [Mn(OCPA)(H2O)]n (9) (4,4′-bipy = 4,4′-bipyridine) were synthesized by hydrothermal methods. The results of structural analyses reveal that the giant structural divergence of the compounds with same metal ions mainly originated from the different amounts of 4,4′-bipy used in syntheses. For Cu-containing compounds, the structural divergences are from one-dimensional (1D) chain 1 to two-dimensional (2D) network 2; for Co, through binuclear 3 to 1D ladder-like 4, and to another different 1D ladder-like chain 5; for Ni, from binuclear 6 to 1D chain 7. But for Zn and Mn, 1D chain 8 and 2D network 9 are obtained with the presence of excess 4,4′-bipy. Compound 9 crystallizes in chiral space group P21 with a second harmonic generation (SHG) efficiency of 0.8 times that of urea. The magnetic studies show that compounds 1 and 9 have antiferromagnetic coupling between the adjacent metallic ions. Compound 4 is a weak ferromagnet based on antiferromagnetic interaction and spin canting. Both the bifurcation temperature of the field-cooled (FC) and zero-field-cooled (ZFC) and the peaks of the real χM′ and the imaginary χM″ parts of alternating current (AC) magnetic susceptibilities are observed at 2.2 K, indicated that the critical temperature Tc is 2.2 K. A very little hysteresis loop is observed with a small coercive field of 20 Oe.
Co-reporter:Ming Fang, Peng-Fei Shi, Bin Zhao, Dong-Xue Jiang, Peng Cheng and Wei Shi
Dalton Transactions 2012 vol. 41(Issue 22) pp:6820-6826
Publication Date(Web):20 Apr 2012
DOI:10.1039/C2DT30391D
Seven lanthanide–cobalt heterometallic three-dimensional coordination polymers: {[Ln3Co2(BPDC)5(HBPDC)(H2O)5](ClO4)2·mH2O}n (Ln = Eu (1, m = 10.25), Gd (2, m = 8), Tb (3, m = 9.5), Dy (4, m = 11), Ho (5, m = 10.5), Tm (6, m = 11), Lu (7, m = 10.25); BPDC = 5,5′-dicarboxylate-2,2′-dipyridine anion) were structurally and magnetically characterized. Compounds 1–7 crystallize in the orthorhombic space group Pbca, featuring a 3D sandwich framework. Magnetic properties of 2–6 have been investigated by using DC (direct current) and AC (alternating current) susceptibility measurements. Among these compounds, only compound 4 displays significant frequency dependence, albeit without reaching the characteristic maxima above 2 K, implying slow magnetic relaxation behavior in 4. After the application of a DC field, good peak shapes of AC signals were obtained and the energy barrier ΔE/kB = 62.89 K and the preexponential factor τ0 = 6.16 × 10−8 s. To our knowledge, 4 has the highest energy barrier in Ln–Co SMM systems hitherto.
Co-reporter:Peng-Fei Shi;Dr. Yan-Zhen Zheng;Dr. Xiao-Qing Zhao;Gang Xiong;Dr. Bin Zhao;Fan-Fan Wan;Dr. Peng Cheng
Chemistry - A European Journal 2012 Volume 18( Issue 47) pp:15086-15091
Publication Date(Web):
DOI:10.1002/chem.201202412
Abstract
Two 3D heterometal–organic frameworks based on infrequent trigonal bipyramidal Ln5 clusters as nodes were structurally and magnetically characterized (Ln=Gd (1), Dy (2)). The results indicate large MCE of up to 30.7 J kg−1 K−1 in 1 and slow magnetic relaxation behavior in 2. Expectedly, constructing 3D MOFs based on multinuclear clusters as nodes may will be a new strategy for achieving large −ΔSm. Additionally, compound 1 exhibits high thermal and solvent stabilities, providing a favorable foundation for realistic applications.
Co-reporter:Xiao-Qing Zhao, Ping Cui, Bin Zhao, Wei Shi and Peng Cheng
Dalton Transactions 2011 vol. 40(Issue 4) pp:805-819
Publication Date(Web):13 Dec 2010
DOI:10.1039/C0DT00516A
The structures, luminescent and magnetic properties of three series of coordination polymers with formulas-{[Fe3Ln2(L1)6(H2O)6]·xH2O}n (Ln = Pr-Er; 1–9), {[Co3Ln2(L1)6(H2O)6]·yH2O}n (Ln = Pr-Dy, Yb; 10–17) and {[Co2Ln(L2)(HL2)2(H2O)7]·zH2O}n (Ln = Eu-Yb; 18–25) (H2L1 = pyridine-2,6-dicarboxylic acid, H3L2 = 4-hydroxyl-pyridine-2,6-dicarboxylic acid) were systematically explored in this contribution. [FeIIHS–L1–LnIII] (1–9) and [CoII–L1–LnIII] (10–17) series are isostructural, and display 3D porous networks with 1D nanosized channels constructed by Fe/Co-OCO-Ln linkages. Furthermore, two types of “water” pipes are observed in 1D channels. [CoII–L2–LnIII] (18–25) series exhibit 2D open frameworks based on double-stranded helical motifs, which are further assembled into 3D porous structures by intermolecular hydrogen bonds between hydroxyl groups. The variety of the resulting structures is mainly due to the HO-substitution effect. These 3D coordination polymers show considerably high thermal stability, and do not decomposed until 400 °C. The high-spin FeII ion in [FeIIHS–L1–LnIII] was confirmed by X-ray photoelectron spectroscopy, Mössbauer spectroscopy and magnetic studies. The luminescent spectra of coordination polymers associated with SmIII, EuIII, TbIII and DyIII were systematically investigated, and indicate that different d-metal ions in d-f systems may result in dissimilar luminescent properties. The magnetic properties of [FeIIHS–L1–LnIII] (3, 6, 7, 9, 13), [CoII–L1–LnIII] (15–17) and [CoII–L2–LnIII] (19–24) coordination polymers were also studied, and the χMT values decrease with cooling. For the single ion behavior of CoII and LnIII ions, the magnetic coupling nature between FeIIHS/CoII and LnIII ions cannot be clearly depicted as antiferromagnetic coupling.
Co-reporter:Ping Cui, Zhi Chen, Dongliang Gao, Bin Zhao, Wei Shi, and Peng Cheng
Crystal Growth & Design 2010 Volume 10(Issue 10) pp:4370-4378
Publication Date(Web):August 31, 2010
DOI:10.1021/cg100467p
Six novel CdII-based metal−organic frameworks with a flexible ligand 1,5-bis(5-tetrazolo)-3-oxapentane) (H2btz), [Cd5(N3)6(btz)2]n (1), [Cd5X2(N3)4(btz)2]n (X = Cl (2), Br (3)), [Cd3(N3)2(btz)2]n (4), and [Cd3X2(btz)2]n (X = Cl (5), Br (6)), have been successfully synthesized under hydrothermal reactions and structurally characterized by single-crystal X-ray diffraction. The H2btz ligands in the complexes 1−4 can be in situ generated from the [2 + 3]-cycloaddition reaction of the precursor bis(2-cyanoethyl)ether (BCEE) and NaN3 under CdII-catalyzed. Single-crystal X-ray diffraction analysis revealed that all of the complexes 1−6 displayed rich three-dimensional (3D) frameworks constructed from Cd2+, btz2− ligand, and bridging anions. It has been found that the ingenious changes of anions finally lead to the structural diversity in 1−6, such as N3− for 1 and 4, N3− and Cl− for 2, N3− and Br− for 3, Cl− for 5, and Br− for 6. Additionally, the X-ray powder diffraction (XRPD), thermal stability, and the photoluminescence properties at room temperature in the solid state for 1−6 have also been studied.
Co-reporter:Li-Min Zhao, Bin Zhai, Dong-Liang Gao, Wei Shi, Bin Zhao, Peng Cheng
Inorganic Chemistry Communications 2010 Volume 13(Issue 9) pp:1014-1017
Publication Date(Web):September 2010
DOI:10.1016/j.inoche.2010.05.018
Three new nickel(II) complexes [Ni2(btec)(azopy)2(H2O)8]·2H2O (1), {[Ni(H2btec)(azopy)(H2O)2]·(azopy)}n (2) and {[Ni4(btec)2(azopy)3(H2O)10]·8H2O}n (3) (H4btec = 1,2,4,5-benzenetetracarboxylic acid; azopy = 4,4′-azobispyridine) have been synthesized by tuning the reaction temperature and the metal–ligand ratio. They were characterized by single-crystal X-ray diffraction and elemental analysis. 1 shows a binuclear structure, 2 exhibits a 2D grid, and 3 features an interesting 3D framework with (63)(4.62)(42.62.82) topology formed by two types of interlocked 2D layers.Three new nickel(II) complexes [Ni2(btec)(azopy)2(H2O)8]·2H2O (1), {[Ni(H2btec)(azopy)(H2O)2]·(azopy)}n (2) and {[Ni4(btec)2(azopy)3(H2O)10]·8H2O}n (3) (H4btec = 1,2,4,5-benzenetetracarboxylic acid; azopy = 4,4′-azobispyridine) have been synthesized by tuning the reaction temperature and the metal–ligand ratio. 1 shows a binuclear structure, 2 exhibits a 2D grid, and 3 features an interesting 3D network with (63)(4.62)(42.62.82) topology formed by two types of interlocked 2D layers.
Co-reporter:Zhi Chen, Bin Zhao, Peng Cheng, Xiao-Qing Zhao, Wei Shi and You Song
Inorganic Chemistry 2009 Volume 48(Issue 8) pp:3493-3495
Publication Date(Web):March 18, 2009
DOI:10.1021/ic801507g
Two lanthanide−organic frameworks, {Ln(TDA)1.5(H2O)2}n [TDA = thiophene-2,5-dicarboxylic acid anion; Ln = Gd (1), Dy (2)], were structurally and magnetically characterized. The magnetic studies revealed that the ferromagnetic coupling existed between adjacent lanthanide ions in 1 and 2, and only 2 displays slow magnetic relaxation behavior with τ0 = 2.4 × 10−8 s and ΔE/kB = 44.2 K. To our knowledge, it is rather rare that ferromagnetic coupling and slow magnetic relaxation coexist in three-dimensional lanthanide-based frameworks.
Co-reporter:Xiao-Qing Zhao ; Bin Zhao ; Shi Wei ;Peng Cheng
Inorganic Chemistry 2009 Volume 48(Issue 23) pp:11048-11057
Publication Date(Web):November 5, 2009
DOI:10.1021/ic901291b
A series of Ln−Ag heterometal−organic frameworks based on 4-hydroxylpyridine-2,6-dicarboxylic acid (H3CAM) with formulas {LaAg2(CAM)(HCAM)(H2O)2}n (1), {LnAg(HCAM)2(H2O)3}n (Ln = Pr, 2; Nd, 3; Sm, 4; Eu, 5), and {LnAg3(CAM)2(H2O)}n (Ln = Gd, 6; Tb, 7; Dy, 8; Tm, 9; Yb, 10), have been synthesized with the hydrothermal reaction of Ln(OH)3, Ag2O, and H3CAM at 160 °C. The single-crystal X-ray diffraction analyses reveal that three kinds of structures are exclusively governed by the size of lanthanide ions and the progression of structures is mainly ascribed to the lanthanide contraction effect. Compound 1 consists of a 3D network with an α-polonium-like Ag+-homometallic net and helical La3+ chain. Compounds 2−5 display a 2D honeycomb-like structure with 18-membered Ln3Ag3O12 motifs, and compounds 6−10 can be described as a sandwich-like 3D framework built of a 3D Ag+-homometallic net and 2D Ln3+−44 layer. In 4 (Sm), 5 (Eu), 7 (Tb), and 8 (Dy) samples, the efficient energy transfer from CAM to Ln(III) ions was observed, which results in the typical intense emissions of corresponding Ln(III) ions in the visible region, and the strongest emissions are 4G5/2 → 6H7/2 (602 nm), 5D0 → 7F2 (614 nm), 5D4 → 7F5 (548 nm), and 4F9/2 → 6H13/2 (576 nm) transitions. Variable-temperature magnetic susceptibility measurements of 6−10 show that the ferromagnetic interaction between gadolinium(III) ions appears in 6, whereas the μeff values of 7−10 smoothly decrease on cooling. For the orbital contribution of Ln(III) ions, it is very difficult to determine the intrinsic magnetic interactions between Ln(III) ions.
Co-reporter:Xiao-Qing Zhao, Ya Zuo, Dong-Liang Gao, Bin Zhao, Wei Shi and Peng Cheng
Crystal Growth & Design 2009 Volume 9(Issue 9) pp:3948-3957
Publication Date(Web):August 7, 2009
DOI:10.1021/cg9000818
Ten novel LnIII−BaII heterometal-organic frameworks, {[Ln2Ba2(PDA)5(H2O)12]·mH2O}n (Ln = Pr (1, m = 9); Sm (2, m = 6); PDA = pyridine-2,6-dicarboxylic anion), {[LnBa1.5(PDA)3(H2O)8]·2H2O}n (Ln = Eu (3); Gd (4); Tb (5)), {[Ln4Ba6(PDA)12(H2O)x]·mH2O}n (Ln = Dy (6, x = 27.5, m = 12); Lu (7, x = 27, m = 11.5)), {[Eu4Ba4(PDA)10(H2O)23]·16H2O}n (3a), {[TbBa3(PDA)4(NO3)(H2O)6]·2H2O}n (5a), and {[DyBa1.5(PDA)3(H2O)7]·2H2O}n (6a), have been successfully synthesized under hydrothermal conditions, and the various structures are constructed from 1D chain, 2D layer, to 3D framework. Compounds 1 and 2 exhibit 1D ribbonlike structures. Compounds 3−5 display 2D layers constructed by 1D BaII chains and [Ln(PDA)3] units. Compounds 6 and 7 exhibit complicated 2D structures different from those of 3−5. When the amount of Ba(OH)2 changes during the syntheses of 3, 5, and 6, three novel coordination polymers 3a, 5a, and 6a were obtained. Compound 3a consists of a 1D chain different from those in 1 and 2. Compound 5a displays a 3D framework, which was constructed through the 2D Ba layers and [Tb(PDA)3] linkers. Compound 6a is isostructural to those of 3−5, although synthetic conditions are different from each other. The significant differences in structure from 1 to 7, and from 3a to 6a, may result from the lanthanide contraction effect, whereas the structural divergences between 3 and 3a, 5 and 5a, and 6 and 6a originate from different amounts of Ba(OH)2 in the synthetic process. The luminescence studies of 2, 3, 5, 6, 3a, 5a, and 6a were applied in the solid state at room temperature, showing intense characteristic emission bands of lanthanide ions, and the results reveal that PDA ligand as an “antenna” may effectively sensitize the luminescence of lanthanide ions.
Co-reporter:Ming Fang, Lixian Chang, Xuhui Liu, Bin Zhao, Ya Zuo and Zhi Chen
Crystal Growth & Design 2009 Volume 9(Issue 9) pp:4006-4016
Publication Date(Web):July 24, 2009
DOI:10.1021/cg900146y
Eight novel lanthanide−organic frameworks, [Ln(CDA)] (Ln = Pr (1), Nd (2), Sm (3), CDA = 4-hydroxypyran-2,6-dicarboxylate), [Ho(CDA)(H2O)] (4), [Pr(HCDA)(C2O4)0.5(H2O)2] (5), [Lu(CDA)Ba2(C2O4)2(H2O)2]·0.25CH3OH (6), [Dy(HCAM)2(CAM)Ba2(H2O)9.75]·7.625H2O ((7), CAM = 4-hydroxypyridine-2,6-dicarboxylate), [Sm2(CAM)4Ba3(H2O)2] (8), have been synthesized under hydrothermal conditions. They were structurally characterized by single-crystal X-ray diffraction. Compounds 1−3 are isostructural and display novel three-dimensional (3D) architectures, and compound 4 features a two-dimensional (2D) double-layer structure. The structural divergence between 1−3 and 4 may originate from a lanthanide contraction effect. By increasing the temperature during the synthesis of 1, CDA was partly decomposed into oxalate ions, and as a result, compound 5 with a 3D framework different from that of 1 was obtained. The Lu-based compound isostructural to 4 has not been obtained so far under synthetic conditions similar to that of 1−4. However, by replacing LiOH with Ba(OH)2, heterometallic [LuBa] compound 6 was successfully synthesized, exhibiting a 3D framework. After changing CDA into CAM based on the synthesis of 6, compounds 7 with a one-dimensional (1D) chain and 8 with a sandwich-like 3D structure were produced. Luminescence analyses were performed on compounds 7 and 8, which exhibit the characteristic transitions of corresponding lanthanide ions. The magnetic susceptibilities of 5 and 7 were measured and discussed.
Co-reporter:Ming Fang, Bin Zhao, Ya Zuo, Jun Chen, Wei Shi, Jing Liang and Peng Cheng
Dalton Transactions 2009 (Issue 37) pp:7765-7770
Publication Date(Web):31 Jul 2009
DOI:10.1039/B903737C
Six heterometal–organic frameworks, {[LnCu1.5(BPDC)3(H2O)2]·mH2O}n (Ln = Gd (1, m = 4.75), Tb (2, m = 3.75), Eu (3, m = 5), Ho (4, m = 2), Yb (5, m = 2.25), BPDC = 4,4′-dicarboxylate-2,2′-dipyridine anion), and {[LuCu1.5(BPDC)3(H2O)1.5]·2.5H2O}n (6), have been synthesized under hydrothermal conditions. The structure analyses for 1–6 reveal that the six compounds are isomorphous, belonging to the monoclinic system with space groupC2/c, and display two-fold interpenetrating 3D frameworks, which are the first examples of d–f heterometal–organic frameworks based on a rigid ligand. These frameworks were further characterized by elemental analyses, TG analysis, PXRD, hydrogen adsorption and variable-temperature magnetic susceptibilities. Interestingly, hydrogen adsorption was significantly observed under the existence of the two-fold interpenetration. Magnetic investigations suggest that the ferromagnetic coupling exists between Gd3+ and Cu2+ in 1, and that the nature of the interaction between Ln3+ and Cu2+ ions in compounds 2, and 4–6 cannot be absolutely determined when χMT values are reduced with decreasing temperature.
Co-reporter:Xiao-Qing Zhao, Bin Zhao, Wei Shi and Peng Cheng
CrystEngComm 2009 vol. 11(Issue 7) pp:1261-1269
Publication Date(Web):02 Mar 2009
DOI:10.1039/B900430K
Eight new 4f–4d heterometallic coordination polymers have been synthesized using pyridine-2,6-dicarboxylic acid (H2PDA) as ligand under hydrothermal conditions. {[PrAg(PDA)2(H2O)3]·2.5H2O}n (1) comprises a 2D grid-like net, and the grid structure is assembled through a Pr4Ag2 motif as the building block. The subsequent six complexes [LnAg(PDA)2(H2O)3]·3H2O}n (Ln = Ce3+, 2; Nd3+, 3; Sm3+, 4; Eu3+, 5; Tb3+, 6; Dy3+, 7) are 1D double-chain coordination polymers. In 2–7, the Ln3+ and Ag+ ions are linked by carboxylic O bridges to form the helical chains, while the right-handed and left-handed chains are linked through carboxylic O bridges to form the double-helical chain. Additionally, the lattice H2O molecules linked by hydrogen bonds construct the helical water chain. {[CeAg2(PDA)3(Py)4]·H2O}n (8) (Py = pyridine) contains one Ce4+ ion and displays a 1D wave-like chain, in which partial H2PDA ligands were decomposed to pyridine. Luminescent studies reveal that the emission intensity of 7 significantly increases with the introduction of Mg2+ ions into the system of 7, whereas the addition of other metal ions causes emission intensity to remain the same or even decrease. Therefore, complex 7 may serve as a luminescent probe of Mg2+.
Co-reporter:Zhi Chen;Ping Cui;Yang Zhang
Science Bulletin 2009 Volume 54( Issue 23) pp:4296-4302
Publication Date(Web):2009 December
DOI:10.1007/s11434-009-0597-1
Four novel lanthanide-based coordination polymers, [Ln(PBDC)(HPBDC)(H2O)3] (H2PBDC=p-carboxylphenoxyacetate; Ln = La (1), Pr (2), Nd (3)) and [La2(PBDC)3(H2O)4] (4), have been prepared through hydrothermal synthetic methods. Compounds 1–3 are isomorphous and exhibit one-dimensional (1D) chain-like motifs, while compound 4 features a complicated three-dimensional (3D) architecture, which is designed and synthesized based on the inspiration from the structure characterization of compound 1. Under the similar reaction conditions, the carboxyl in compound 1 may be further deprotonated by adding the organic base of 2,2′-bipyridine. This subtle change caused a significant difference in the structures, from 1D chain of 1 to a 3D structure of 4. In addition, IR, UV-Vis, TGA and magenetic properties are also investigated in this paper.
Co-reporter:Li Wang ; Lixian Chang ; Bin Zhao ; Zhongyong Yuan ; Gaosong Shao ;Wenjun Zheng
Inorganic Chemistry 2008 Volume 47(Issue 5) pp:1443-1452
Publication Date(Web):January 18, 2008
DOI:10.1021/ic701094a
In this contribution, a series of shape-controllable ZnO nanostructures were synthesized in ionic liquids by a simpler, only one-step, low-temperature route, and characterized by XRD, XPS, TEM, HRTEM, SAED, EDXA, SEM, FTIR, surface area measurement and photoluminescence. We mainly investigate the effect of cations of ionic liquids on the shape of ZnO nanostructures and the forming mechanism of ZnO nanostructures in ionic liquids, as well as the luminescent property and photocatalytic activity for the degradation of Rhodamine B. The results show that the longer alkyl chain at position-1 of the imidazole ring of the ionic liquid will hinder the ZnO nanostructures from growing longer, and the hydrogen bonds may play a crucial role for the directional growth of the 1D nanocrystals. The photoluminescent study shows that the as-obtained ZnO nanostructures exhibit a unique green emission, indicating the existence of oxygen vacancies in the ZnO nanostructures. Importantly, the as-obtained ZnO nanostructures prepared in different ionic liquids show strong size/shape-dependent photocatalysis activity for degradation of Rhodamine B, and the well-dispersed homogeneous ZnO nanoparticles and nanowires display high photocatalytic activity. The investigation of photodegradation kinetics of Rhodamine B indicates that the photodegradation process obeys the rule of a first-order kinetic equation ln(C0/C) = kt. This is the first systematic investigation on the relationship between the structure of ionic liquids and the morphology of ZnO nanostructures.
Co-reporter:Zhi Chen, Bin Zhao, Yang Zhang, Wei Shi and Peng Cheng
Crystal Growth & Design 2008 Volume 8(Issue 7) pp:2291
Publication Date(Web):June 12, 2008
DOI:10.1021/cg700988s
Five novel lanthanide−organic frameworks: [Ln(NTA)(H2O)2]·H2O (Ln = Eu (1)) and [Ln(NTA)(H2O)] (Ln = Tb (2), Ho (3, 4), and Tm (5); NTA = nitrilotriacetate anion) have been constructed by a rational synthetic strategy. 1 and 5 were successfully obtained by tuning the number of coordinated water molecules to lanthanide ions under different temperatures, while 2 and 3 were prepared under the same synthetic temperature as that of 5. Structural analyses indicate that they belong to three different space groups. 1 displays an irregular two-dimensional (2D) lattice consisting of alternative L- and R-type single-chain helixes, and both 2 and 3 are 2D double layer structures, while 4 and 5 are porous three-dimensional (3D) frameworks. Surprisingly, although 3 and 4 have identical molecular formulas, their structures exhibit significant differences originating from different pH values used in the synthesis. Interestingly, one-dimensional (1D) channels exist in the 3D frameworks of 4 and 5; each channel is fabricated through interweaving left- and right-hand triple-stranded helixes. The explorations of magnetic properties of 2 and 5 were carried out. The luminescent investigations reveal that 2 exhibits characteristic luminescence of Tb3+, and the lifetime of the transition 5D4 → 7F5 is about 0.78 ms when excited at λex = 296 nm.
Co-reporter:Zhi Chen, Ya Zuo, Xiu-Hua Li, Hui Wang, Bin Zhao, Wei Shi, Peng Cheng
Journal of Molecular Structure 2008 Volume 888(1–3) pp:360-365
Publication Date(Web):15 October 2008
DOI:10.1016/j.molstruc.2007.12.040
Two novel coordination polymers associated with indium and cadmium ions respectively, {[In(TCA)(OH)(H2O)]}n (1) and {[Cd(TCA)(H2O)3] · 4H2O}n (2) (H2TCA = thiophene-2,5-dicarboxylic acid), were prepared under hydrothermal conditions, and characterized by the single-crystal X-ray diffraction, element analysis, IR and luminescence spectra. Compound 1 displayed an interesting 2D lattice structure, consisted of indium ions, OH− anions and TCA ligands. In 2, seven coordinated cadmium ions were bridged by TCA ligands to generate 1D chain. The luminescent properties for 1, 2 and the TCA ligand have also been explored.
Co-reporter:Zhi-Lei Wu, Jie Dong, Wei-Yan Ni, Bo-Wen Zhang, Jian-Zhong Cui and Bin Zhao
Dalton Transactions 2014 - vol. 43(Issue 44) pp:NaN16845-16845
Publication Date(Web):2014/09/15
DOI:10.1039/C4DT02427C
Two novel tetra- and deca-nuclear dysprosium compounds, namely, [Dy4(μ3-OH)2(L)10(bipy)2(H2O)2]n (1) and {[Dy10(μ3-OH)8(L)22(bipy)2(H2O)2]·5H2O}n (2) (L = 3-fluoro-4-(trifluoromethyl)benzoic acid; bipy = 2,2′-bipyridine), have been successfully obtained by hydrothermal reaction at different pH values. The solid state structures of 1 and 2 were established by the single crystal X-ray diffraction technique, and both of them exhibit complicated 1D chains with [Dy4] (1) and [Dy10] (2) cluster units, respectively. Adjacent [Dy4] in 1 and [Dy10] in 2 are connected by two bridging carboxylate groups in the η1:η1:μ2 mode. Magnetic studies reveal that they exhibit different magnetic relaxation behaviors with the energy barrier of 23.6 K for 1 and 3.2 K for 2. Interestingly, the large divergence in both the structures and magnetic properties for 1 and 2 only originated from the different pH values in preparing them.
Co-reporter:Bo Shen, Peng-Fei Shi, Yin-Ling Hou, Fan-Fan Wan, Dong-Liang Gao and Bin Zhao
Dalton Transactions 2013 - vol. 42(Issue 10) pp:NaN3463-3463
Publication Date(Web):2012/11/27
DOI:10.1039/C2DT32515B
Five novel compounds {[Cu(CMA)]·0.8H2O}n (1), {[Cu(CMA)(bpy)0.5]·0.5DMF}n (2), {[Cu(CMA)(bpy)(H2O)]·0.5H2O}n (3), {[Cu2(CMA)(DPA)(bpy)2(H2O)]ClO4}n (4) and {[Cu3(CMA)(DPA)(bpy)4(OH)](ClO4)2·3H2O)}n (5) (H2CMA = 3-(carboxymethoxy)-5-methylbenzoic acid, HDPA = 2-(3,5-dimethylphenoxy)acetic acid, bpy = 4,4′-bipyridine) were synthesized and characterized by single crystal X-ray diffraction. Interestingly, the kinds of ligands included in these compounds are different: 1 contains single-ligand CMA2−; 2 and 3 comprise two kinds of ligands (CMA2− and bpy); 4 and 5 cover three kinds of ligands (CMA2−, DPA− and bpy). Structural analyses reveal that 1–3, and 5 are three-dimensional (3D) frameworks, while 4 is a 2D layer. Noteworthily, 1 possesses two types of channels: six-star and hexagonal ones. 3 displays a three-fold interpenetrating 3D framework. The structural diversity of the compounds may have originated from different anions, solvents and temperatures. Variable-temperature magnetic susceptibility measurements were carried out on compounds 1, 2 and 4, and the magnetic properties are dramatically different due to the structural diversities. The magnetic data of 1 shows an antiferromagnetic interaction with J = −54.84 cm−1 estimated from the Bonner–Fisher model. The magnetic data of 2 was least-square fitted to the Blenaey–Bowers equation with J = −131.01 cm−1, indicating the existence of a strong antiferromagnetic interaction between two adjacent Cu2+. The magnetic data of linear tetranuclear structure 4 was best fitted to the expression derived from the Hamiltonian H = −2(2J1S1S2 + J2S1S1*). The best fitting parameters are J1 = −17.48 cm−1 and J2 = −65.26 cm−1, which also indicate an antiferromagnetic interaction. Simultaneously, the magneto-structural relationship was discussed.
Co-reporter:Hang Xu, Chun-Shuai Cao, Xiao-Min Kang and Bin Zhao
Dalton Transactions 2016 - vol. 45(Issue 45) pp:NaN18017-18017
Publication Date(Web):2016/07/14
DOI:10.1039/C6DT02213H
Lanthanide-based metal–organic frameworks (Ln-MOFs), as notable materials, are constructed by Ln3+ ions and organic ligands, or Ln3+ ions functionalizing non-Ln-MOFs, and exhibit promising applications in various fields. Over the past decades, quite a lot of investigations of Ln-MOFs have been carried out, and many good results have been obtained. Among these results, Ln-MOFs as luminescent probes for unique detection are gradually becoming a hot topic due to their fast and effective luminescent response for the targeted substance. In this perspective article, we discuss the construction of luminescent Ln-MOFs, their applications in possible detection mechanisms, and summarize some examples of Ln-MOFs as luminescent probes for sensing cations, anions and small molecules.
Co-reporter:Gang Xiong, Bing Yu, Jie Dong, Ying Shi, Bin Zhao and Liang-Nian He
Chemical Communications 2017 - vol. 53(Issue 44) pp:NaN6016-6016
Publication Date(Web):2017/05/10
DOI:10.1039/C7CC01136A
Investigations on metal–organic frameworks (MOFs) as direct catalysts have been well documented, but direct catalysis of the chemical conversion of terminal alkynes and CO2 as chemical feedstock by MOFs into valuable chemical products has never been reported. We report here two cluster-based MOFs I and II assembled from a multinuclear Gd-cluster and Cu-cluster, displaying high thermal and solvent stabilities. I and II as heterogeneous catalysts possess active catalytic centers [Cu12I12] and [Cu3I2], respectively, exhibiting excellent catalytic performance in the carboxylation reactions of CO2 with 14 kinds of terminal alkynes under 1 atm and mild conditions. For the first time catalysis of the carboxylation reaction of terminal alkynes with CO2 by MOF materials without any cocatalyst/additive is reported. This work not only reduces greenhouse gas emission but also provides highly valuable materials, opening a wide space in seeking recoverable catalysts to accelerate the chemical conversion of CO2.
Co-reporter:Wen-Min Wang, Shi-Yu Wang, Hong-Xia Zhang, Hai-Yun Shen, Ji-Yong Zou, Hong-Ling Gao, Jian-Zhong Cui and Bin Zhao
Inorganic Chemistry Frontiers 2016 - vol. 3(Issue 1) pp:NaN141-141
Publication Date(Web):2015/11/10
DOI:10.1039/C5QI00192G
Three dinuclear Dy(III) complexes, [Dy2(tfa)4L2] (1), [Dy2(TTA)4L2] (2) and [Dy2(dbm)4L2·2CH3CN·0.5H2O] (3) (tfa = trifluoroacetylacetonate, TTA = 2-thenoyltrifluoroacetone, dbm = dibenzoylmethane and HL = 2-[((4-bromophenyl)-imino)methyl]-8-hydroxyquinoline, have been synthesized, and structurally and magnetically characterized. The Dy(III) ions are eight-coordinated with two bidentate β-diketonate and two μ2-O bridging 8-hydroxyquinoline Schiff base ligands. Magnetic studies reveal that 1–3 exhibit different magnetic relaxation behaviors with the anisotropic barriers of 9.61 K (1), 54.81 K (2) and 30.98 K (3), respectively. The different magnetic relaxation behaviors of the three Dy2 complexes originate from the different chemical environments of the central Dy3+ ions with different β-diketonate coligands.
Co-reporter:Hang Xu, Chun-Shuai Cao and Bin Zhao
Chemical Communications 2015 - vol. 51(Issue 51) pp:NaN10283-10283
Publication Date(Web):2015/04/21
DOI:10.1039/C5CC02596F
A novel 3D Eu-BTB framework (1) containing three types of 1D channels was synthesized and structurally characterized. Compound 1 exhibits high thermostability and water stability with the pH range from 2 to 12. Additionally, the luminescence explorations revealed that 1 can sensitively and selectively detect pollutant PO43− among various colourless anions. More importantly, 1 represents the first example of regenerable MOF-based luminescent probes for detecting PO43−.
Co-reporter:Peng-Fei Shi, Huan-Cheng Hu, Zhan-Yun Zhang, Gang Xiong and Bin Zhao
Chemical Communications 2015 - vol. 51(Issue 19) pp:NaN3988-3988
Publication Date(Web):2015/01/08
DOI:10.1039/C4CC09081K
Two cationic heterometal–organic frameworks (Eu-Zn (1·NO3−) and Tb-Zn (2·NO3−)) with NO3− counter-anions in the channels are structurally and luminously characterized. Both of them can serve as highly sensitive and highly selective luminescent probes for detecting I− ions in aqueous solutions. In particular, 2·NO3− can selectively and reversibly detect I− with a fast response time of just 10 s and an extremely low detection limit of 0.001 ppm. Mechanism studies reveal that I− is quickly oxidized to form I3− with the help of 1·NO3− or 2·NO3−, leading to luminescence quenching. This represents the first report of MOF-based luminescent probes for the detection of I− in aqueous solutions.
Co-reporter:Gang Xiong, Xiang-Yang Qin, Peng-Fei Shi, Yin-Ling Hou, Jian-Zhong Cui and Bin Zhao
Chemical Communications 2014 - vol. 50(Issue 32) pp:NaN4257-4257
Publication Date(Web):2014/01/28
DOI:10.1039/C3CC49342C
Two unique heptanuclear clusters Ln@Zn6 (Ln = Dy (1), Er (2)) were structurally and magnetically characterized. Each Dy3+/Er3+ is located in a nona-coordinate D3h coordination environment, and is encapsulated in a diamagnetic Zn6 cage. Compound 1 exhibits single-ion magnetic behavior, and is the first example of a single-ion magnet (SIM) constructed through embedding one magnetic anisotropic metal ion into a diamagnetic cage.
Co-reporter:Yin-Ling Hou, Gang Xiong, Peng-Fei Shi, Rui-Rui Cheng, Jian-Zhong Cui and Bin Zhao
Chemical Communications 2013 - vol. 49(Issue 54) pp:NaN6068-6068
Publication Date(Web):2013/05/14
DOI:10.1039/C3CC42545B
Two unique 3D coordination polymers based on octahedral [Ln6] (Ln = Gd (1), Dy (2)) clusters as nodes were synthesized, exhibiting a novel (3,12)-connected topology with the symbol of (420·626·820)(43)4. The magnetic studies reveal that 1 shows a −ΔSm = 46.6 J kg−1 K−1, falling among the largest values known to date, and 2 displays slow magnetic relaxation behavior. Both 1 and 2 have high thermal and solvent stabilities.
Co-reporter:Ming Fang, Ji-Jing Li, Peng-Fei Shi, Bin Zhao and Peng Cheng
Dalton Transactions 2013 - vol. 42(Issue 18) pp:NaN6563-6563
Publication Date(Web):2013/02/13
DOI:10.1039/C3DT32861A
Eight three-dimensional lanthanide–organic frameworks: [Ln(BPDC)1.5(DMF)(H2O)2]·2H2O (Ln = Eu (1), Gd (2), Tb (3), Dy (4); BPDC = 4,4′-dicarboxylate-2,2′-dipyridine anion), [Ln(BPDC)(DMF)2(NO3)] (Ln = Eu (5), Gd (6), Tb (7), Dy (8)) were fabricated and structurally characterized. Compounds 1–4 are isostructural, belonging to the triclinic system with space group P, while compounds 6–8 belong to the monoclinic system with space group C2/c. Structural differences between two types of compounds may be caused by different reaction conditions. Magnetic properties of 2–4 and 6–8 have been investigated and only compounds 4 and 8 display significant frequency-dependence, albeit without reaching the characteristic maxima above 2 K, implying slow magnetic relaxation behaviors in 4 and 8. After the application of a DC field, good peak shapes of AC signal were obtained and got the energy barrier for 4, ΔE/kB = 79.80 K and the pre-exponential factor τ0 = 1.28 × 10−10 s, for 8, ΔE/kB = 38.15 K and τ0 = 2.47 × 10−9 s. Geometrical differences in the crystal fields of Dy3+ in 4 and 8 seem to be responsible for the large divergence of their magnetic behaviors. Luminescence analyses were performed on coordination polymers containing Eu3+, Tb3+, and Dy3+, which exhibit the characteristic transitions of corresponding lanthanide ions, and give the lifetime (τ0) of 1, 3, 4, 5, 7 and 8 are 0.56 ms, 0.89 ms, 8.48 μs, 0.60 ms, 0.75 ms and 36.35 μs, respectively.
Co-reporter:Ming Fang, Bin Zhao, Ya Zuo, Jun Chen, Wei Shi, Jing Liang and Peng Cheng
Dalton Transactions 2009(Issue 37) pp:NaN7770-7770
Publication Date(Web):2009/07/31
DOI:10.1039/B903737C
Six heterometal–organic frameworks, {[LnCu1.5(BPDC)3(H2O)2]·mH2O}n (Ln = Gd (1, m = 4.75), Tb (2, m = 3.75), Eu (3, m = 5), Ho (4, m = 2), Yb (5, m = 2.25), BPDC = 4,4′-dicarboxylate-2,2′-dipyridine anion), and {[LuCu1.5(BPDC)3(H2O)1.5]·2.5H2O}n (6), have been synthesized under hydrothermal conditions. The structure analyses for 1–6 reveal that the six compounds are isomorphous, belonging to the monoclinic system with space groupC2/c, and display two-fold interpenetrating 3D frameworks, which are the first examples of d–f heterometal–organic frameworks based on a rigid ligand. These frameworks were further characterized by elemental analyses, TG analysis, PXRD, hydrogen adsorption and variable-temperature magnetic susceptibilities. Interestingly, hydrogen adsorption was significantly observed under the existence of the two-fold interpenetration. Magnetic investigations suggest that the ferromagnetic coupling exists between Gd3+ and Cu2+ in 1, and that the nature of the interaction between Ln3+ and Cu2+ ions in compounds 2, and 4–6 cannot be absolutely determined when χMT values are reduced with decreasing temperature.
Co-reporter:Huan-Cheng Hu, Chun-Shuai Cao, Yang Yang, Peng Cheng and Bin Zhao
Journal of Materials Chemistry A 2015 - vol. 3(Issue 14) pp:NaN3499-3499
Publication Date(Web):2015/02/20
DOI:10.1039/C4TC02958E
A novel triangular [Mn3] cluster-based 3D ferrimagnet [Na2Mn3(SO4)3(μ3-OH)2(μ2-OH2)2]n (1) was structurally and magnetically characterized. It exhibited both long-range magnetic ordering (TC = 12.0 K) and spin glass behaviour around 10 K and a butterfly-shaped magnetic hysteresis loop was observed. A peak (14.4 J kg−1 K−1) in the −ΔSmvs. temperature curve was obtained at 13.5 K. It is rather rare that the magnetocaloric effect of a ferrimagnet was explored and that the peak in the −ΔSmvs. temperature curve occurs above 10 K.
Co-reporter:Xiao-Qing Zhao, Ping Cui, Bin Zhao, Wei Shi and Peng Cheng
Dalton Transactions 2011 - vol. 40(Issue 4) pp:NaN819-819
Publication Date(Web):2010/12/13
DOI:10.1039/C0DT00516A
The structures, luminescent and magnetic properties of three series of coordination polymers with formulas-{[Fe3Ln2(L1)6(H2O)6]·xH2O}n (Ln = Pr-Er; 1–9), {[Co3Ln2(L1)6(H2O)6]·yH2O}n (Ln = Pr-Dy, Yb; 10–17) and {[Co2Ln(L2)(HL2)2(H2O)7]·zH2O}n (Ln = Eu-Yb; 18–25) (H2L1 = pyridine-2,6-dicarboxylic acid, H3L2 = 4-hydroxyl-pyridine-2,6-dicarboxylic acid) were systematically explored in this contribution. [FeIIHS–L1–LnIII] (1–9) and [CoII–L1–LnIII] (10–17) series are isostructural, and display 3D porous networks with 1D nanosized channels constructed by Fe/Co-OCO-Ln linkages. Furthermore, two types of “water” pipes are observed in 1D channels. [CoII–L2–LnIII] (18–25) series exhibit 2D open frameworks based on double-stranded helical motifs, which are further assembled into 3D porous structures by intermolecular hydrogen bonds between hydroxyl groups. The variety of the resulting structures is mainly due to the HO-substitution effect. These 3D coordination polymers show considerably high thermal stability, and do not decomposed until 400 °C. The high-spin FeII ion in [FeIIHS–L1–LnIII] was confirmed by X-ray photoelectron spectroscopy, Mössbauer spectroscopy and magnetic studies. The luminescent spectra of coordination polymers associated with SmIII, EuIII, TbIII and DyIII were systematically investigated, and indicate that different d-metal ions in d-f systems may result in dissimilar luminescent properties. The magnetic properties of [FeIIHS–L1–LnIII] (3, 6, 7, 9, 13), [CoII–L1–LnIII] (15–17) and [CoII–L2–LnIII] (19–24) coordination polymers were also studied, and the χMT values decrease with cooling. For the single ion behavior of CoII and LnIII ions, the magnetic coupling nature between FeIIHS/CoII and LnIII ions cannot be clearly depicted as antiferromagnetic coupling.
Co-reporter:Xiao-Qing Zhao, Xu-Hui Liu and Bin Zhao
Dalton Transactions 2013 - vol. 42(Issue 41) pp:NaN14793-14793
Publication Date(Web):2013/08/08
DOI:10.1039/C3DT51769A
A series of lanthanide-based organic frameworks with formulas of {[PrL(H2O)2]·2H2O}n (1) and {[Ln3L3(H2O)2]·2H2O}n (Ln = Eu (2), Gd (3), Tb (4), Dy (5), Ho (6), Er (7); H3L = 4-(carboxymethoxy)isophthalic acid), were hydrothermally synthesized and structurally characterized. It is the first time that 4-(carboxymethoxy)isophthalic acid is employed in producing lanthanide compounds. The seven compounds exhibit two types of structures with the decreasing radius of the lanthanide ions, representing the lanthanide contraction effect. Compound 1 with the large Pr3+ ion displays a 2D layered structure with a binodal (4,4)-connected topology with the Schläfli symbol of (3363)2, whereas compounds 2–7 with small Ln3+ ions feature a 3D framework constructed from carboxyl groups with a (5,6,8)-connected topology with the Schläfli symbol of (324454)·(34445463)·(344856698). The luminescence and magnetic properties were investigated, and the results indicate that the H3L ligand can sensitize the lanthanide luminescence in compounds 2, 4 and 5 and makes a contribution to the antiferromagnetic interactions in compound 3 or the uncertain magnetic interactions in compounds 4–7. Additionally, the thermal analyses suggest the high thermal stability of compounds 1–7.
Co-reporter:Ming Fang, Hanhua Zhao, Andrey V. Prosvirin, Dawid Pinkowicz, Bin Zhao, Peng Cheng, Wolfgang Wernsdorfer, Euan K. Brechin and Kim R. Dunbar
Dalton Transactions 2013 - vol. 42(Issue 41) pp:NaN14701-14701
Publication Date(Web):2013/08/01
DOI:10.1039/C3DT51727F
A series of isostructural octanuclear lanthanide complexes of general formula [Ln8(sao)4(μ3-OH)4(NO3)12(DMF)12] (Ln = Nd (1), Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Ho (7), Er (8); DMF = dimethylformamide) have been prepared via reactions of salicylaldoxime (saoH2), tetramethylammonium hydroxide (Me4NOH) with the appropriate lanthanide nitrate salt (Ln(NO3)3·6H2O). The metallic skeletons of the complexes describe [Ln4] tetrahedra encapsulated inside a [Ln4] square with the inner core stabilised through μ3-OH− ions and the periphery by μ4-sao2− ligands. The magnetic properties of compounds 2–8 were investigated by dc and ac magnetometry. Temperature dependent ac magnetic susceptibility data reveal that the dysprosium analogue (6) displays an out-of-phase signal in the absence of an applied magnetic field indicative of slow relaxation of the magnetization typical of a Single-Molecule Magnet (SMM). Micro-SQUID measurements reveal temperature and sweep rate dependent hysteresis below 1.0 K.
Co-reporter:Ming Fang, Peng-Fei Shi, Bin Zhao, Dong-Xue Jiang, Peng Cheng and Wei Shi
Dalton Transactions 2012 - vol. 41(Issue 22) pp:NaN6826-6826
Publication Date(Web):2012/04/20
DOI:10.1039/C2DT30391D
Seven lanthanide–cobalt heterometallic three-dimensional coordination polymers: {[Ln3Co2(BPDC)5(HBPDC)(H2O)5](ClO4)2·mH2O}n (Ln = Eu (1, m = 10.25), Gd (2, m = 8), Tb (3, m = 9.5), Dy (4, m = 11), Ho (5, m = 10.5), Tm (6, m = 11), Lu (7, m = 10.25); BPDC = 5,5′-dicarboxylate-2,2′-dipyridine anion) were structurally and magnetically characterized. Compounds 1–7 crystallize in the orthorhombic space group Pbca, featuring a 3D sandwich framework. Magnetic properties of 2–6 have been investigated by using DC (direct current) and AC (alternating current) susceptibility measurements. Among these compounds, only compound 4 displays significant frequency dependence, albeit without reaching the characteristic maxima above 2 K, implying slow magnetic relaxation behavior in 4. After the application of a DC field, good peak shapes of AC signals were obtained and the energy barrier ΔE/kB = 62.89 K and the preexponential factor τ0 = 6.16 × 10−8 s. To our knowledge, 4 has the highest energy barrier in Ln–Co SMM systems hitherto.
Co-reporter:Yin-Ling Hou, Gang Xiong, Bo Shen, Bin Zhao, Zhi Chen and Jian-Zhong Cui
Dalton Transactions 2013 - vol. 42(Issue 10) pp:NaN3596-3596
Publication Date(Web):2012/11/27
DOI:10.1039/C2DT32390G
Six novel three-dimensional (3D) lanthanide metal–organic frameworks (LnMOFs), {[Ln2(ispc)3(H2O)3]·mH2O}n (Ln = Pr (1, m = 5); Eu (2, m = 5); Gd (3, m = 4); Tb (4, m = 5); Dy (5, m = 5) and Ho (6, m = 4)), ispc = 3-(4-carboxyphenylsulfonyloxy)-4-methoxybenzoic anion) have been synthesized under hydrothermal conditions. Single crystal X-ray diffraction revealed they are isostructural and crystallize in the triclinic crystal system, space group P. The investigations on luminescent properties and lifetimes of 2 (EuIII), 4 (TbIII), and 5 (DyIII) exhibit characteristic emissions of EuIII, TbIII and DyIII ions and the corresponding luminescent lifetimes are 0.14 ms, 9.93 μs and 1.25 ms, respectively. The different luminescent intensities and lifetimes among them were further discussed. Furthermore, magnetic studies of 1–6 reveal that 3–6 exhibit ferromagnetic coupling, and 5 (DyIII) exhibits remarkably slow magnetic relaxation behavior with the energy barrier ΔE/kB = 49.2 K.
Co-reporter:Gang Xiong, Hang Xu, Jian-Zhong Cui, Qing-Lun Wang and Bin Zhao
Dalton Transactions 2014 - vol. 43(Issue 15) pp:NaN5642-5642
Publication Date(Web):2014/01/20
DOI:10.1039/C3DT53251H
Triple core–shell structures in the Cu24Gd6 and Cu24Dy6 clusters were first observed and structurally characterized. The magnetic investigations reveal that Cu24Gd6 possesses the significant magnetic entropy change (−ΔSm) of 21.2 J kg−1 K−1 for ΔH = 7 T, and a slow magnetization relaxation is observed in Cu24Dy6.
Co-reporter:Yin-Ling Hou, Rui-Rui Cheng, Gang Xiong, Jian-Zhong Cui and Bin Zhao
Dalton Transactions 2014 - vol. 43(Issue 4) pp:NaN1820-1820
Publication Date(Web):2013/10/15
DOI:10.1039/C3DT52305E
Through hydrothermal reactions with corresponding lanthanide nitrates and 4-(4-carboxyphenylsulfonyloxy)-3-metnoxybenzoic acid (H2vspc), seven novel three-dimensional (3D) lanthanide–organic frameworks ([Ln(vspc)(Hvspc)(H2O)]n [Ln = Pr (1), Eu (2), Gd (3), Tb (4), Dy (5), Ho (6) and Er (7)]) have been synthesized and structurally characterized. All of them are isostructural and crystallize in the monoclinic crystal system, P21/c space group. Their structures feature a (3,6)-connected topological network, in which Ln3+ were connected by carboxylate groups to give a 1D lanthanide chain, and the adjacent chains are further spanned by vspc2− and Hvspc− anions to form a 3D framework. The luminescent properties and lifetimes of 2 (EuIII), 4 (TbIII), and 5 (DyIII) have been studied, and the corresponding luminescent lifetimes are 0.53, 0.99 and 0.014 ms, respectively. The magnetic investigations reveal that compound 3 displays weak antiferromagnet interaction, 4 and 5 exhibit ferromagnetic coupling, and compound 5 exhibits slow magnetic relaxation behavior.
Co-reporter:Xiao-Qing Zhao, Xu-Hui Liu, Xiao-Min Kang and Bin Zhao
Dalton Transactions 2015 - vol. 44(Issue 43) pp:NaN18863-18863
Publication Date(Web):2015/09/29
DOI:10.1039/C5DT02280K
A family of heterometallic 4f–3d coordination polymers with the common formula [LnCo1.5(L)2(H2O)5]n (Ln = Pr(1), Eu(2), Gd(3), Tb(4), Dy(5), Ho(6), and Er(7), and H3L = 4-(carboxymethoxy)isophthalic acid) was obtained under solvothermal conditions with the effect of NaN3, which was involved in the reactions but not in the final structure. All of the compounds were isostructural, and had a two-dimensional wave-like structure based on centrosymmetric [LnO2Co]–Co–[LnO2Co] motifs. The results of the magnetic measurements displayed that ferromagnetic interactions occurred in the frameworks (3–7) containing “heavy” lanthanide ions (Gd, Tb, Dy, Ho, and Er), which should be ascribed to the coupling between the LnIII and CoII ions. Furthermore, compound 5, containing DyIII ions, displayed field-induced slow magnetic relaxation.
Co-reporter:Zhi Chen, Ming Fang, Xiao-Min Kang, Yin-Ling Hou and Bin Zhao
Dalton Transactions 2016 - vol. 45(Issue 1) pp:NaN88-88
Publication Date(Web):2015/11/13
DOI:10.1039/C5DT02444G
A dinuclear Dy(III) compound (1) was structurally and magnetically characterized, displaying a single-molecule magnet (SMM) behavior with a relaxation energy barrier of 21(1) K. Interestingly, by only adding a suitable substituent on the ligand in 1, 1 as an SMM building unit, can be further assembled into a two-dimensional (2D) framework (2), which possesses a typical SMM behavior and a high relaxation energy barrier of 68(2) K. The result implied that the assembly of an SMM can effectively tune the energy barrier. To our knowledge, a cluster-based SMM assembled into a new 2D framework with SMM behavior is seldom reported.
Co-reporter:Wen-Min Wang, Wan-Zhen Qiao, Hong-Xia Zhang, Shi-Yu Wang, Yao-Yao Nie, Hong-Man Chen, Zhen Liu, Hong-Ling Gao, Jian-Zhong Cui and Bin Zhao
Dalton Transactions 2016 - vol. 45(Issue 19) pp:NaN8191-8191
Publication Date(Web):2016/04/04
DOI:10.1039/C6DT00220J
Nine dinuclear Ln(III) complexes, [Ln(dbm)2(L)]2 (Ln = Eu (1), Tb (2), Dy (3), Ho (4), Er (5)) and [Ln(dbm)2(L′)]2 (Ln = Tb (6), Dy (7), Ho (8), Er (9)) (dbm = 1,3-diphenyl-1,3-propanedione, HL = 2-[[(4-methoxy-phenyl)imino]methyl]-8-hydroxy-quinoline and HL′ = 2-[[(4-ethoxyphenyl)imino]methyl]-8-hydroxyquinoline) have been synthesized, and structurally and magnetically characterized. The nine complexes are all phenoxo-O bridged binuclear complexes, in which Ln1 and Ln1a are in an eight-coordinated environment bridged by two phenoxido oxygen atoms of two 8-hydroxyquinoline Schiff base ligands. Although complexes 3 and 7 have very similar structures, magnetic studies reveal that they exhibit different magnetic relaxation behaviors with the effective barriers (ΔE/kB) of 34.5 K for 3 and 67.6 K for 7. The dissimilar dynamic magnetic behaviors of 3 and 7 mostly result from the different electron-donating effect induced by the two alkoxy (–OCH3 and –OC2H5) of the 8-hydroxyquinoline Schiff base ligands. Meanwhile, for complexes 2, 5, 6 and 9, there are no observed magnetic relaxation behaviors under a zero dc field. In addition, the luminescence properties of 1, 2 and 6 were studied.
Co-reporter:Peng-Fei Shi, Bin Zhao, Gang Xiong, Yin-Ling Hou and Peng Cheng
Chemical Communications 2012 - vol. 48(Issue 66) pp:NaN8233-8233
Publication Date(Web):2012/06/28
DOI:10.1039/C2CC33707J
We present one 3D cationic MOF (1-ClO4), which exhibits high thermal stability and strong alkali resistance. More importantly, it displays fast, selective capture of, and acts as a luminescent probe for, pollutant CrO42− by anion exchange. Additionally, 1-ClO4 exhibits interesting slow magnetic relaxation behavior at low temperature.
Co-reporter:Peng-Fei Shi, Gang Xiong, Bin Zhao, Zhan-Yun Zhang and Peng Cheng
Chemical Communications 2013 - vol. 49(Issue 23) pp:NaN2340-2340
Publication Date(Web):2013/02/04
DOI:10.1039/C3CC38402K
Two novel Dy–Cu MOFs were structurally and magnetically characterized. The results reveal that it is the first example of anion-induced change of structure interpenetration and magnetic properties in 3d–4f MOFs.
Co-reporter:Li-Xian Chang, Gang Xiong, Li Wang, Peng Cheng and Bin Zhao
Chemical Communications 2013 - vol. 49(Issue 11) pp:NaN1057-1057
Publication Date(Web):2012/10/29
DOI:10.1039/C2CC35800J
Two 24-nuclear lanthanide clusters, Gd24 and Dy24 were obtained and structurally characterized. Magnetic investigations reveal that Gd24 exhibits the largest entropy change (−ΔSm) of 46.12 J kg−1 K−1 for ΔH = 7 T in all reported molecular clusters, and single-molecule magnet behaviour is observed in Dy24.
Co-reporter:Yin-Ling Hou, Hang Xu, Rui-Rui Cheng and Bin Zhao
Chemical Communications 2015 - vol. 51(Issue 31) pp:NaN6772-6772
Publication Date(Web):2015/03/10
DOI:10.1039/C5CC01181G
Two novel 3D frameworks were synthesized, and further nanosized to form nanospheres. Studies revealed that 2 is the first MOF-based luminescent sensor for detecting cyclohexane, and this is also the first time that quick regeneration, high sensitivity, high yield, and easy nanocrystallization of MOF-based luminescent sensors have been simultaneously realized.
Co-reporter:Huan-Cheng Hu, Xiao-Min Kang, Chun-Shuai Cao, Peng Cheng and Bin Zhao
Chemical Communications 2015 - vol. 51(Issue 54) pp:NaN10853-10853
Publication Date(Web):2015/06/01
DOI:10.1039/C5CC03670D
A novel 3D tetrazole-bridged 3d–4f heterometallic MOF {(H3O)3[Gd3Mn2(Trz)4]·12H2O}n (1) with a hexanuclear [Gd6] cluster was obtained via in situ [2+3] cycloaddition reaction and structurally characterized, possessing good solvent and thermal stabilities, as well as a large magnetic entropy change −ΔSm = 40.3 J kg−1 K−1 for ΔH = 7 T at 2.0 K. To our knowledge, it is the first example of tetrazole-bridged 3d–4f heterometallic MOFs.
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![1,3-Dioxolan-2-one,4-[(phenylmethoxy)methyl]-](http://img.cochemist.com/ccimg/1000/949-97-3_b.png)
![1,3-Benzenedicarboxylic acid, 5,5'-[1,2-ethanediylbis(oxy)]bis-](/data/chemimg/2310900/52739-95-4.png)
![1,3-Benzenedicarboxylic acid, 5,5'-[1,2-ethanediylbis(oxy)]bis-](/data/chemimg/2310900/52739-95-4_b.png)
![Zinc, diaqua[[2,2'-bipyridine]-4,4'-dicarboxylato(2-)-κN1,κN1']-, (T-4)-](http://img.cochemist.com/data/images/1251838-65-9.png)
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![4-([2,2':6',2''-Terpyridin]-4'-yl)benzoic acid](/data/chemimg/104300/158014-74-5.png)
![4-([2,2':6',2''-Terpyridin]-4'-yl)benzoic acid](/data/chemimg/104300/158014-74-5_b.png)
![1H-1,2,4-Triazole, 1,1'-[1,4-phenylenebis(methylene)]bis-](/data/chemimg/105500/143131-66-2.png)
![1H-1,2,4-Triazole, 1,1'-[1,4-phenylenebis(methylene)]bis-](/data/chemimg/105500/143131-66-2_b.png)
