Color Centers in Alkaline Earth Fluorides

Abstract

Several experiments are presented dealing with color centers in alkaline earth fluorides. Evidence for simple color centers is not observed. Color centers previously reported in Ca${\mathrm{F}}_2$ are due to the contamination of fluorite with Y. The optical and electron paramagnetic resonance spectra of ${\mathrm{Y}}^{2+}\left(4\mathrm{}{d}^1\right)$ are discussed.