Semirelativistic technique for k.p calculations: Optical properties of Pd and Pt
Abstract
A semirelativistic twocomponent extended linear augmented planewave k.p method is described. In order to ensure a high accuracy of the k.p method, it is necessary to include into the radialbasis set, which is used for the augmentation of the plane waves, functions that are neither solutions of the Schrödinger equation nor their energy derivatives. The usual scalar relativistic procedure, which is nonlinear in energy, is not applicable to such basis sets. As an alternative, we suggest an approximation to the FoldyWouthuysen Hamiltonian that produces an explicitly Hermitean matrix in the augmented plane wave representation. The technique is applied to the calculation of the full dielectric matrix and optical properties of palladium and platinum metals over the photon energy region up to 100 eV. Special attention is paid to the far ultraviolet absorption by the excitations of semicore Pd 4p and Pt 5p and 4f states. A strong effect of local fields is observed in the far UV region.
 Publication:

Physical Review B
 Pub Date:
 June 2001
 DOI:
 10.1103/PhysRevB.63.235112
 Bibcode:
 2001PhRvB..63w5112K
 Keywords:

 71.15.Ap;
 78.40.q;
 71.15.Rf;
 Basis sets and related methodology;
 Absorption and reflection spectra: visible and ultraviolet;
 Relativistic effects