Experiments on Er3+ in SrF2. II. Concentration Dependence of Site Symmetry

Abstract

Electron spin resonance has been used to follow the changes of site symmetry that occur in rare-earth-doped SrF2. The main conclusions that may be drawn are that the variation of site from tetragonal to trigonal as one goes through the rare-earth series Ce3+ to Er3+ can be explained by a calculation of the relative energies of interstitial fluorine ions and that the concentration dependence of the trigonal and cubic sites of Er3+-doped SrF2 can be explained by the sweeping action of dislocations for both the charge compensating and erbium ions.