Satellite lines in the paramagnetic resonance spectra of impurities in calcium fluoride

Abstract

In the electron spin resonance spectra of some lanthanon impurities in CaF 2 the lines are flanked by satellites which are due to transitions in which a neighbouring fluorine nucleus flips with the electron. The theory of these transitions is discussed and applied to the analysis of the satellite structure in the spectrum of Ce 3+ in CaF 2 . It appears that the coupling between the electron and the fluorine ion includes some s -contact character. There is evidence for the presence of a neighbouring interstitial fluorine ion to compensate for the extra positive charge on the Ce 3+ ion.