Linear optical properties of solids within the full-potential linearized augmented planewave method

We present a scheme for the calculation of linear optical properties by the all-electron full-potential linearized augmented planewave (LAPW) method. A summary of the theoretical background for the derivation of the dielectric tensor within the random-phase approximation is provided. The momentum matrix elements are evaluated in detail for the LAPW basis, and the interband as well as the intra-band contributions to the dielectric tensor are given. As an example the formalism is applied to Aluminum. The program is available as a module within the WIEN2k code.