Spin-orbit coupling within a two-component density functional theory approach: Theory, implementation and first applications

An implementation of spin-orbit coupling within a two-component generalization of the density functional code MAGIC is described. The spin-orbit operator is represented in the effective one-electron mean-field approximation and included into the Fock matrix within an iterative self-consistent scheme. First tests have been carried out for the spin-orbit splitting of several atoms. The spin-orbit effect on the bond distance and harmonic frequency of some diatomics has also been determined. This scheme allows to include spin-orbit in a simple way and can be efficiently used to treat large systems.