X-ray absorption near-edge structure in alpha-quartz and stishovite: Ab initio calculation with core–hole interaction

Ab initio calculation of the XANSE/ELNES spectra for α quartz and stishovite were carried out using a large-supercell approach that includes the electron–core–hole interaction. Excellent agreements with experimental spectra were obtained for Si–K, Si–L2,3, and O–K edges. The usual interpretation using orbital-resolved local density of states in the conduction band is unsatisfactory.