L2,3 EDGES OF TETRAHEDRALLY COORDINATED D(0) TRANSITION-METAL OXYANIONS XO4N-

The L2,3 edges of compounds containing tetrahedrally coordinated, isoe lectronic d0 transition-metal oxyanions, TiO4(4-), VO4(3-), CrO4(2-) a nd MnO4- have been measured using electron energy-loss spectroscopy (E ELS). The general shape of the electron energy-loss near-edge fine str ucture (ELNES) is found to be remarkably similar for these oxyanions a nd arises from the atomic multiplet spectrum of the d0 transition-meta l ion modified by the tetrahedral field due to the oxygen ligands. The observed structure is also discussed within the framework of molecula r-orbital (MO) theory. The possibilities of using these spectra as fin gerprints for do transition-metal ions in tetrahedral coordination is discussed. The structure observed at the 0 K edges is also commented u pon in the light of these findings.