The controlled organization of high-spin complexes into 1D coordination polymers is a challenge in molecular magnetism. In this work, we report a ferromagnetic Mn trimer Mn3(HL)2(CH3OH)6(Br)4·Br·(CH3OH)21 (H2L = 2-[(9H-fluoren-9-yl)amino]propane-1,3-diol) with the ground spin state of ST = 7 that can be assembled into a one-dimensional coordination chain [Mn3(HL)2(CH3OH)2(Br)4(N3)(H2O)·CH3OH]∞2 using azido bridging ligands. Interestingly, the ferromagnetic nature of 1 is well retained in 2. However, due to the negligible magnetic anisotropy in 1, both 1 and 2 do not show slow-relaxation of magnetization, which indicates that during the process of molecular assembly not only the intratrimer magnetic interaction but also the magnetic anisotropy of the trimer can be reserved.

Target synthesis of metal–organic nanotubes (MONTs) through a classic “rolling-up” mechanism remains a big challenge for coordination chemists. In this work, we report three 2D lamellar compounds and one (4,0) zigzag MONT based on a common honeycomb coordination skeleton. Our synthetic strategy toward sheet/tube superstructure transformation is to asymmetrically modify the inter-layer interactions by gradually increasing the size of the amine templates. Eventually, to relieve the surface tension of individual layers and to enhance surface areas and optimize host–guest interactions to accommodate bigger guests, spontaneous rolling up to form a tubular structure was achieved.

Controlled organization of high-spin complexes and single-molecule magnets is a great challenge in molecular magnetism in order to study the effect of the intercomplex magnetic interactions on the intrinsic properties of a given magnetic object. In this work, a new ST = 7 trinuclear mixed-valence Mn complex, [MnIIIMnII2(LA)2(Br)4(CH3OH)6] ·Br·(CH3OH)1.5·(H2O)0.5 (1), is reported using a pyridinium-functionalized 1,3-propanediol ligand (H2LABr = 1-(3-bromo-2,2-bis(hydroxymethyl)propyl)pyridinium bromide). Using azido anions as bridging ligands and different pyridinium-functionalized 1,3-propanediol ligands (H2LBBr = 1-(3-bromo-2,2-bis(hydroxymethyl)propyl)-4-picolinium bromide; H2LCBr = 1-(3-bromo-2,2-bis(hydroxymethyl)propyl)-3,5-lutidinium bromide), the linear [MnIIIMnII2L2X4]+ building block has been assembled into one-dimensional coordination networks: [MnIIIMnII2(LA)2(Br)4(CH3OH)4(N3)]·((C2H5)2O)1.25 (2∞), [MnIIIMnII2(LB)2(Br)4(C2H5OH)(CH3OH)(H2O)2(N3)]·(H2O)0.25 (3∞), and [MnIIIMnII2(LC)2(Cl)3.8(Br)0.2(C2H5OH)3(CH3OH)(N3)] (4∞). The syntheses, characterization, crystal structures, and magnetic properties of these new [Mn3]-based materials are reported.

The controlled organization of high-spin complexes, eventually single-molecule magnets, is a great challenge in molecular sciences to probe the possibility to design sophisticated magnetic systems to address a large quantity of magnetic information. The coordination chemistry is a tool of choice to make such materials. In this work, high-spin ST = 22 [Mn10] complexes, such as [MnIII6MnII4(L1)6(μ4-O)4(μ3-N3)4(CH3CN)11(H2O)]·(ClO4)2·(CH3CN)8.5 (1), have been assembled using (i) 1,3-propanediol derivatives as chelating ligands to form the [Mn10] core units and (ii) dicyanamide or azide anions as linkers to synthesize the first 2D and 3D [Mn10]-based networks: [MnIII6MnII4(L2)6(μ3-N3)4(μ4-O)4(CH3OH)4(dca)2] (2) and [MnIII6MnII4(L3)6(μ3-N3)4(μ4-O)4(N3)2]·(CH3OH)4 (3). The synthesis of these compounds is reported together with their single-crystal X-ray structures and magnetic properties supported by DFT calculations. In the reported synthetic conditions, the stability of the [Mn10] complex is remarkably good that allows us to imagine many new materials combining these high-spin moieties and other diamagnetic but also paramagnetic linkers to design for example ordered magnets.

The design of new polynuclear transition metal complexes showing large total spin values through parallel alignment of the spins is an important challenge due to the scarcity of bridging ligands that provide ferromagnetic coupling. Herein, we report two new complexes, a [MnII4MnIII2] system containing two non-linear [MnII2MnIII] units and a 1D chain system with [MnII2MnIII] units that are assembled through dicyanamide bridging ligands coordinated to one of the terminal MnII centers. In both cases, the main exchange interaction is between MnII⋯MnIII, showing a relatively strong ferromagnetic coupling. Density functional theory calculations corroborate such ferromagnetic interactions and also provide one magnetostructural correlation, showing that larger MnII–O–MnIII angles enhance the strength of the ferromagnetic coupling. Thus, the non-linear [MnII2MnIII] units present in these two complexes are specially suited because of their larger MnII–O–MnIII angles compared to similar previously reported systems containing a linear [MnII2MnIII] unit. Introduction to the international collaboration The collaboration between Dr Wu's and Professor Ruiz's groups performs research on the synthetic chemistry of transition metal complexes with magnetic properties (Jilin University) and utilizes computational tools (University of Barcelona) to gain further insight into the nature of the physical properties of these systems. In this study, the interaction between our groups focused on the study of polynuclear systems containing an [MnII2MnIII] motif displaying ferromagnetic couplings. Such exchange pathways are needed to reach a large total spin value, which is one of the requirements to design single-molecule magnets. Thus, the synthesis of polynuclear complexes by Wu's group and subsequent density functional theory (DFT) calculations by the Ruiz group were performed in order to determine all the exchange interaction constants, corroborating the experimental data and provide further insight into the magnetic behavior of these systems. Previous collaborations between our groups included a similar approach for the study of [Mn10] cluster systems also showing ferromagnetic behavior due to MnII–MnIII interactions.

The controlled organization of high-spin complexes into 1D coordination polymers is a challenge in molecular magnetism. In this work, we report a ferromagnetic Mn trimer Mn3(HL)2(CH3OH)6(Br)4·Br·(CH3OH)21 (H2L = 2-[(9H-fluoren-9-yl)amino]propane-1,3-diol) with the ground spin state of ST = 7 that can be assembled into a one-dimensional coordination chain [Mn3(HL)2(CH3OH)2(Br)4(N3)(H2O)·CH3OH]∞2 using azido bridging ligands. Interestingly, the ferromagnetic nature of 1 is well retained in 2. However, due to the negligible magnetic anisotropy in 1, both 1 and 2 do not show slow-relaxation of magnetization, which indicates that during the process of molecular assembly not only the intratrimer magnetic interaction but also the magnetic anisotropy of the trimer can be reserved.