STUDY OF INTERMEDIATE OXIDES IN SNO THERMAL-DECOMPOSITION

Two series of room temperature x-ray and Mossbauer spectroscopy (MS) measurements were performed on powder SnO samples after 1 h annealing in air and Ar at temperatures between 473 and 1073 K in 100 K steps. Complementary measurements on one SnO sample treated in vacuum in this sequence were performed after the thermal treatment at 773 K. In the thermal evolution between SnO and SnO2 the results show the presence of an intermediate oxide not only in the Ar and vacuum annealed samples but also in those annealed in air. The Mossbauer parameters of the 2+ and 4+ states for the intermediate oxide were determined. The results were consistent with a reaction rate dependent on the oxygen partial pressure.