An ab initio calculation is presented for the refractive indices and Szigeti charge of 12 alkali halide solids. The polarizabilities of the anions and cations are calculated separately, and the refractive indices are obtained from the Clausius-Mosotti relation. The Szigeti charge is obtained by a calculation of the deformation dipole parameters. Both the polarizabilities and deformation dipole parameters are calculated with use of the local-density approximation. The parameters are found for each ion where the crystalline environment is simulated by a cage of pseudopotentials. The results agree well with experimental data.

• Received 10 April 1986

DOI:https://doi.org/10.1103/PhysRevB.34.4235