Vibronic Structure in the Absorption Spectrum of theCe+3Ion in CaF2

Abstract

A high-resolution absorption spectrum of the lowest $4f\to 5d$ transition of ${\mathrm{Ce}}^{+3\mathrm{}}$ in Ca${\mathrm{F}}_2$ is presented showing a rich vibronic structure. The observed structure leads to an entirely different interpretation of the spectrum from that proposed by Loh.