Synthesis, reactivity, x-ray structure and thermal study of the mixed-metal oxide hydrate [Mn(H2O)(2)V2O6]

The mixed-metal oxide hydrate Mn(H2O)(2)V2O6 (1) has been prepared by the r eaction of potassium vanadate with manganese chloride tetrahydrate in aqueo us reaction medium at 70 - 72 degrees C. The orange-red crystals of (1) hav e been characterized by FT-IR, Raman, and UV-VIS spectroscopy, thermogravim etric analysis, magnetic susceptibility measurement, and complete single cr ystal x-ray structure analysis. The structure of (1) consists of the stacks of zigzag chains of corner sharing {VO4} tetrahedra cross-linked by {MnO4( H2O)(2)} octahedral units generating a complex Mn/O/V/O network. The struct ure exhibits cavities and tunnels delimited by four and six polyhedra. Ther mal treatment of (1) under nitrogen atmosphere results into the removal coo rdinated water. The dehydrated samples of (1) exhibits reversible water abs orption. Observed room temperature magnetic moment (5.87 BM) of (1) is cons istent with the presence of high-spin Mn(II) centers. Crystal data for (I): Orthorhombic space group Pnma (No. 62), a = 5.6085(6), b = 10.917(16), c = 12.042(2) Angstrom, V = 7373(2) Angstrom(3), Z = 4. The reactions of (1) w ith some simple ligands is described.