Multiple scattering (Physics)

Within the Green's function approach to the multiple scattering theory, we present a different formalism for the screened Korringa-Kohn-Rostoker (KKR) scheme. In addition, we investigate the convergence properties of the screened KKR by performing total energy and density of states calculations for a fcc copper. Finally, we introduce a new approach to (near) tight binding calculations of the screened tau-matrix that yields total energies within the desired accuracy.

The QKKR method is a recently invented band theory with remarkable advantages of fast computational speed and no special requirements on the one electron potential. It has been successfully applied to the band structure calculation for simple crystals. A program for QKKR band theory calculations for complex crystals (more than one atom per unit cell) is developed and applied to PdH. It is shown that, compared with the KKR method, the QKKR method is more efficient and yields very accurate results in the range of energies in which we are interested. Unlike other band theories, the QKKR requires the expansion of a three dimensional step function in real spherical harmonics. A general method for evaluating this expansion is established in this thesis.