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C103H116O13SiSn4, triclinic, P1‾$\overline{1}$ (no. 2), a = 14.8676(4) Å, b = 17.6664(4) Å, c = 20.8357(6) Å, α = 106.430(2)°, β = 107.192(2)°, γ = 100.898(2)°, V = 4787.5(2) Å3, Z = 2, Rgt(F) = 0.0325, wRref(F2) = 0.0845, T = 150 K.

4-(2,6-Di(2H-indazol-2-yl)pyridin-4-yl)benzoic acid (1) and 10-(2,6-di(1H-pyrazol-1-yl)pyridin-4-yl)anthracene-9-carboxylic acid (2) were required for adsorption studies on Ag(111), with a view to subsequent iron(II) complexation and formation of well-ordered spin-responsive self-assembled monolayers. While the generation of these compounds has remained elusive, several intermediates and by-products were obtained, potentially useful as dipyrazolylpyridine-related derivatives and for metal ion coordination. 3,5-Dichloro-2,6-diindazolylpyridine-4-amine, which forms as a mixture of regioisomers, was synthesised, the mixture separated, and the components characterised (3,5-dichloro-2,6-di(2H-indazol-2-yl)pyridin-4-amine; 3,5-dichloro-2-(1H-indazol-1-yl)-6-(2H-indazol-2-yl)pyridin-4-amine; 3,5-dichloro-2,6-di(1H-indazol-1-yl)pyridin-4-amine). Their iron(II) complexes have been prepared and fully characterised, including single crystal X-ray structure determination. The complexes are instructive examples of the influence of ligand design ("steric jamming") on the spin-crossover (SCO) activity of FeII centres. Bulky substitution, which entails twisted ligand conformation, increases intramolecular crowding. This prevents contraction of the metal coordination sphere, which would be a prerequisite for thermally inducible SCO. Mössbauer spectroscopy has revealed that the complexes remain predominantly high-spin (HS) between 20 and 200 K, and that a mixture of conformational HS isomers is present in the microcrystalline solid. [ABSTRACT FROM AUTHOR]

C103H116O13SiSn4, triclinic, P 1 ‾ $\overline{1}$ (no. 2), a = 14.8676(4) Å, b = 17.6664(4) Å, c = 20.8357(6) Å, α = 106.430(2)°, β = 107.192(2)°, γ = 100.898(2)°, V = 4787.5(2) Å3, Z = 2, R gt (F) = 0.0325, wR ref (F 2) = 0.0845, T = 150 K. [ABSTRACT FROM AUTHOR]

Cu2ZnSiSe4 belong to the adamantine family of quaternary chalcogenides crystallizing in the wurtzstannite structure. Recent ab-initio calculations show, that the lowest energy structure of Cu2ZnSiSe4 is the wurtzkesterite type structure in contrast to wurtzstannite type, usually obtained in experiments. To clarify this issue a structural study on single crystals of Cu2ZnSiSe4 was performed for the first time. The structural characterization of the single crystals was carried out by X-ray diffraction at two different temperatures - room temperature and 150 K. The XRD data analysis shows, that Cu2ZnSiSe4 single crystals adopt the orthorhombic wurtzstannite type structure (space group Pmn21) and lattice parameters a = 7.809 Å, b = 6.778 Å, c = 6.447 Å at 150 K, and lattice parameters a = 7.821 Å, b = 6.734 Å, c = 6.453 Å at room temperature were derived. The structural parameters were confirmed for the polycrystalline Cu2ZnSiSe4 bulk sample. [ABSTRACT FROM AUTHOR]

A new vanadium fluoride hydrate V2F6 ⋅ 4 H2O was prepared by reacting vanadium metal with hexafluorosilicic acid solution. The crystal structure of the green compound was determined by X-ray diffraction. The identified structure of the CuMF6 ⋅ 4 H2O-type (M = Ti, Zr) has not been found amongst vanadium fluoride hydrates to date. In addition, thermal decomposition behaviour and magnetic properties of V2F6 ⋅ 4 H2O were studied. [ABSTRACT FROM AUTHOR]