Reflection spectra of perovskites from 8 eV to 60 eV

Abstract

The reflectivity of KMgF3, and of the antiferromagnets KNiF3, KCoF3, KMnF3 and RbMnF3 has been measured over a wide energy range using synchrotron radiation. There is a dominant excitonic structure in the 10-12 eV region due to charge transfer. There is also a striking demonstration of the ionization of core excitons brought about by using transition metals to lower the conduction band threshold. The XPS spectra of KMgF3, KMnF3 and KNiF3 have been measured, and the last is compared critically with a band structure calculation.