Temperature dependencies of Ni, Cu and Mo metals EXAFS spectra were studied in order to determine the anharmonic pair potential. The potential parameters for metals with cubic structure-Ni, Cu, Mo as well as for Pb (Stern E A et al 1991 Phys. Rev. B 43 8850), Au, Ag (Newville M and Stern E A http://krazy.phys.washington.edu/paper/ag-au.html)-obtained earlier, were analysed to find correlations with other physical characteristics. It was found that a, b potential parameter values correlate with cohesive energy and interatomic distance for face-centred-cubic structure metals. Obtained potential parameter values were used to determine thermodynamics parameters, including the linear coefficient of thermal expansion, the Debye temperature, the bulk modulus and the Grunesien parameter.

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Thermal transformations of Fe Ilt maleate, [Fe30(OOCCH=CHCOOH)6]OH 9 3H20 (1), in an autogenerated atmosphere and the change in the short-range surrounding of Fe atoms during thermolysis were studied. The thermal transformations of 1 are accompanied by the folIowing processes: dehydration with simultaneous rearrangement of the ligand environment and formation of maleic acid, and polymerization of the rearranged monomer and its decarboxylation at high temperatures. In the initial stage of decarboxylation, the destruction of the metal-cat-boxylate FejO complex occurs followed by the formation of the Fe--Fe bond (r = 0.246 nm). The oxidation of the Fe atoms is observed when the thermolysis duration increases.