Absorption and magnetic circular dichroism spectra of CsBr:In+; moments analysis

Optical absorption and magnetic circular dichroism spectra of single crystals of CsBr:In⁺ have been measured at several temperatures in the range from 2.5 to 300 K. The moments of the corresponding lineshape spectra have been determined by numerical integration and, for the absorption spectra, also by band resolution. Good agreement between the results of the two methods is obtained, except at temperatures at which the bands overlap, where numerical integration cannot be expected to yield accurate results. The semiclassical approximation, which has hitherto been applied to the NaCl structure, has been modified for the CsCl structure and used to analyze the temperature dependence of the moments. This analysis yields the effective frequency ω_c of the lattice modes that couple with the excited electronic states. The electron-lattice coupling constants, which characterize the interaction of the electronic states of the impurity ion with lattice vibrations of A_1g, E_g and T_2g symmetry, have been evaluated for the |A> state and the temperature dependence of the orbital g factors $\text{g}$_A and $\text{g}$_B of the A and B bands has been determined.