Thermal decompositions of the molybdotellurates of nickel(II) and cobalt(II)

Molybdotellurates [M(H2O)(6)](3).[TeMo(6)O(2)4], with M=Ni(II) and Co(II), were synthesized and characterized by single-crystal X-ray diffraction for compound 1 and X-ray powder diffraction for compound 2, EDAX, IR, electroni c spectra in the solid phase and in solution, and magnetic properties. Ther mogravimetry and differential scanning calorimetry of both compounds reveal ed a loss of 11 water molecules through an endothermal process with Delta H =800 kJ mol(-1) for the nickel compound and Delta H=833 kJ mol(-1) for the cobalt compound. The residual compounds were characterized by chemical anal ysis, IR and XPS spectroscopy.