Electron paramagnetic resonance and optical spectroscopy of Yb3+ ions in SrF2 and BaF2; an analysis of distortions of the crystal lattice near Yb3+

摘要: SrF2 and BaF2 crystals, doped with the Yb3+ ions, have been investigated by electron paramagnetic resonance optical spectroscopy. As-grown crystals of show two centres for cubic (Tc) trigonal (T4) symmetries ions. Empirical diagrams energy levels were established potentials crystal field determined. Information was obtained on phonon spectra from electron-vibrational structure spectra. The parameters used to analyse lattice distortions in vicinity impurity ion F− compensating excess positive charge T4. Within frames a superposition model, it is shown that three ions nearest surrounding cube, located symmetrically respect C3 axis side ion-compensator, approach cling centre when forming between also approaches close ion.