STRUCTURAL AND CHEMICAL EFFECTS ON THE SIK-BETA X-RAY-EMISSION SPECTRA FOR SILICATES AND SILICOPHOSPHATES

The SIK beta X-ray emission spectra for several silicates and silico-p hosphates were measured using a high-resolution X-ray fluorescence spe ctrometer with two InSb(III) analyser crystals. Molecular orbital calc ulation analysis for the obtained spectra was performed by a SCC-DV-X alpha method and the energy positions and relative intensities of the spectral fine structures were calculated with Slater's transition-stat e method. The calculated results interpreted the spectral profiles suc cessfully. The energy shifts of the SiK beta main peak were also discu ssed in terms of the electronegativity of the second-nearest-neighbour atoms. These shifts were attributed to the changes in the stability o f the Si-O bonds due to the existence of second-nearest-neighbour P at oms.