Abstract
We developed a self-consistent screened-Korringa–Kohn-Rostoker (KKR) method in an ab initio tight-binding formulation. The reduction in numerical effort in comparison with that required for the standard KKR method is achieved by the choice of a suitable reference system. Following the idea of Zeller et al. (1995, Phys. Rev. B, 52, 8807), reference systems with repulsive muffintin potentials of constant height are considered. This paper is dedicated to reference potentials of infinite height, so-called hard core potentials. It will be demonstrated that the advantage of the analytical solution to the scattering problem is accompanied by a reduced accuracy of the screened KKR method for close-packed hard spheres. To overcome this problem, we consider hard spheres with a reduced diameter. The best results also in comparison with reference potentials of finite height are obtained using hard spheres with a radius reduced to about 80% of the muffin-tin value.