Vacuum ultraviolet reflectance and electron energy loss spectra of CaTiO3

Normal incidence light reflection measurements have been performed for CaTiO3 single crystals over the wide energy region from 0.4 to 35 eV. The dielectric functions and optical constants are evaluated from the reflectance spectrum by the Kramers-Kronig transformation technique. The experimental electron energy loss spectrum is in reasonable agreement with the energy loss function calculated from the dielectric functions. In comparison of the dielectric functions with joint density of states, the peaks in the energy region from 3 to 8 eV are mainly attributed to the transition from O 2p to Ti 3d orbitals, and those from 8 to 15 eV are assigned to the transitions from O 2p to Ti 3d, Ca 4s and Ti 4s orbitals.