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Acidity of water molecules coordinated to Co ions in CoFe Prussian blue analogues (PBA) has been used to reversibly activate the Co(III)Fe(II) ↔ Co(II)Fe(III) electron transfer. The study of the structure and the electronic structure shows that the process implies an original PCET reaction between a solid-state porous coordination polymer and hydroxide ions in solution. The PCET reaction spreads throughout the solid network thanks to a long-range H(+) and Rb(+) transport within the pore channels of PBA taking advantage of the hydrogen-bonding network of zeolitic water molecules acting as proton wires.

The seminal discovery in 1981 of bimetallic ferrimagnetic chains, based on the synthetic use of the concept "complex as ligand", can be considered as a significant step on the way from molecules to more and more complex materials. We describe the chemistry, the structures, the magnetic properties of these 1D materials, together with the new theoretical models created to understand them. We then give an overview of some original creative ideas, which have irrigated the synthetic chemistry of brand‐new molecular materials, room temperature magnets, photomagnetic and chiral magnets or functional surfaces. The review emphasizes that the celebrated individual "wins" are indeed the fruit, along the years, of the constructive multidisciplinary collaboration of many scientists, theoreticians and experimentalists, chemists and physicists. Difficulties, dead‐end hypotheses, mistakes which represent a significant exciting part of any scientific endeavour, are not put under the rug. [ABSTRACT FROM AUTHOR]

A magneto-structural study of two salicylamidoxime-based {Mn6} single-molecule magnets revealed that their anisotropy energy barriers, which can reach the current record for d-transition metal complexes, are strongly dependent upon the precise arrangement of ligands and the solvation state. [ABSTRACT FROM AUTHOR]

Abstract: We report the synthesis of several new vanadium–chromium Prussian blue analogues with a Curie temperature above room temperature. A catalytic amount of vanadium(III) during the synthesis allows to get improved magnetic properties, stable Curie temperatures (T C) and a magnetisation at saturation in satisfying agreement with the stoichiometry. The insertion of alkali cations (potassium, rubidium, caesium) allows to reach a V:Cr stoichiometry close to 6:5, hence to enhance the number of magnetic neighbours compared to the usual V:Cr 3:2 stoichiometry and to increase accordingly the Curie temperature. For the same stoichiometry, the ferrimagnetic ordering temperature varies slightly with the nature of the inserted alkali cation (T C/K=360, 346 and 340K for the potassium, rubidium and caesium derivatives, respectively). X-ray absorption spectroscopy allows to characterise the local surroundings of the chromium and vanadium ions and to propose an explanation of the magnetic properties. [Copyright &y& Elsevier]

Abstract: Nine μ-cyanido bridged polynuclear complexes, [Cr(CN) n (CNNiL)6−n ] m+, (with n =0–5 and L=pentadentate ligand), were synthesised: CrNi, five CrNi2, CrNi3, CrNi5 and CrNi6. The compounds have been fully characterised by IR spectroscopy, mass spectrometry and X-ray crystallography. Their magnetic properties have been studied and the spin and the anisotropy values as well as the intra- and inter-molecular exchange couplings evaluated. The spin state varies from 5/2 to 15/2 (ferromagnetic interaction) and the effective anisotropic factor varies from 0 to 0.5cm−1. Experimentally, the exchange coupling between the μ-cyanido bridged spin carriers Cr(III) and Ni(II) varies from +4.5 to +18.3cm−1 increasing with the C–N–Ni angle. A computational study allows to propose a magneto structural correlation and to rationalise the most relevant features of the exchange interaction between Cr(III) () and Ni(II) () through a cyanido bridge. In order to decrease the intermolecular interactions, a dilution of the chromium(III)–nickel(II) compounds with the equivalent cobalt(III)–nickel(II) has been successfully performed by co-crystallisation. [Copyright &y& Elsevier]

Abstract: The design and preparation of stable cyanide-bearing six-coordinate complexes of formula [MIII(L)(CN) x ](x + l − m)− (M=trivalent transition metal ion and L=polydentate blocking ligand) are summarized here. Their use as ligands towards either fully hydrated metal ions or coordinatively unsaturated preformed species, to afford a wide variety of low-dimensional metal assemblies whose nuclearity, dimensionality and magnetic properties can be tuned, is also reviewed. Special emphasis is put on the appropriate choice of the end-cap ligand L whose denticity determines the number of coordinated cyanide groups in the mononuclear precursors. Among the different new spin topologies obtained through this rational synthetic strategy, ferromagnetically coupled 4,2-ribbon like bimetallic chains which exhibit slow magnetic relaxation and hysteresis effects (chain as magnets) are one of the most appealing and constitute the heart of the present contribution. [Copyright &y& Elsevier]

Focuses on the synthesis of optically active three-dimensional (3D) magnets to elucidate the relationship between structural and magnetic properties of molecular materials having both a Cotton effect and ferromagnetic long range order. Design of the optically active 3D molecule-based magnets using the enantioselective template effect of optically active cations; Magnetic circular dichroism.