The Screened or Tight-Binding KKR method can be used to perform all electron, electronic structure calculations using density functional theory. The method is based on multiple scattering theory and the Kohn-Sham equations for a solid are solved by dividing space in cells and connecting the scattering events from each individual cell using Green's function formalism (Dyson equation). You can find general references about the method in the end of this manual.
The present package consists of three main programs, the voronoi, skkr, and impurity. This give you a rather powerful combination for electronic structure calculations of solids. The programs can be used for the calculation of 3D periodic systems, and supercells, 2D finite slabs or 2D semiinfinite systems. Impurities can be embedded in any of the above environments, using the impurity program. The Atomic Sphere Approximation (ASA) but with full charge density or Full potential (FP) calculations are possible. The current version can use simple non relativistic or scalar relativistic formalism. The TB-formulation of the KKR theory allows fast and accurate O(N) scaling calculations for ASA or FP. In the FP space is divide into cells with a Wigner-Seitz construction or more general Voronoi construction. This space division, potential preparation and lattice analysis can be done with the voronoi program. Usually for Density of states, bandstructures, rough estimates of energetics, magnetic moments, etc ASA is enough. For better energies, forces (geometry optimizations, relaxations) full potential has to be used. Defects in bulk, surfaces, interfaces, including energetics etc. can be studied with the impurity program.