Thermal decomposition of irradiated and unirradiated KI O4 and its X.R.D spectra

The thermal decomposition of γ-ray irradiated KI O4 has been studied. The decomposition isotherms reach saturation values at long heating times. Similarly a saturation value has been observed for the decomposition fraction as a function of the exposed γ-ray doses. Kinetic analysis of the irradiated decomposition data shows a decrease in the dimensionality(n) of the reaction from the Avramie-Erofeev equation, compared with the unirradiated KI O4, (n is constant and equals 1.8 for the irradiated and varies between 2 and 3 for the unirradiated; the activation energy is about 1 eV). The effect of γ-ray has been investigated and it was shown that all isotherms reach the same value at different γ-ray doses. X-ray diffraction of KI O4 after removing the outer part of the crystal has been studied to determine the crystallographic variation due to heating and irradiation. The analysis of data shows decrease in the surface area corresponding to the (hkl) plane as function of the decomposition degree and γ-ray dose, i.,e. There is a variation in the concentration of atoms in the (hkl) plane. The positron annihilation has been studied in order to obtain more information about the defects. (author). 20 refs., 8 figs., 1 tab