SOFT-X-RAY-FLUORESCENCE AND INELASTIC-LIGHT-SCATTERING STUDIES OF SOLIDS

Soft x-ray emission (SXE) studies of several semiconductors and early transition metal compounds have been carried out. In the case of trans ition metal compounds, the comparison between photoemission (PES) and SXE spectra shows that the fluorescence spectra are consistent with PE S spectra, but the elastic- and inelastic-light scattering spectra ref lects the initial 3d states which may be related with the charge trans fer state. On the other hand, the inelastic-light (Raman) scattering s pectra of semiconductors have been measured in the energy region corre sponding to the core exciton states. The Raman scattering spectra whos e energy shifts in proportion to the excitation energy are found in th e excitation energy region below the absorption edge. It is found that the Raman scattering of semiconductor emits the valence exciton as an elementary excitation.