Schiekel, Bernhard (20. März 1984): RMAPW-Verfahren und selbstkonsistente Bandstruktur von Gold. Dissertation, Ludwig-Maximilians-Universität München




The "Relativistic Modified Augmented Plane Wave" (RMAPW) method of Bross and Hofmann (1969) was realized numerically in a slightly modified form and tested with the example of copper potential of Burdick (1963). With regard to future applications in the area of surface-bandstructures and surface-states this realization was done in a generalization of the RMAPW-method for complex k-vectors ("complex RMAPW") of Wachutka (1978). Starting from the "Overlapping Charge Density" (OCD) potential of gold in "Muffin Tin" (MT) form from Christensen and Seraphin (1971) in this work a selfconsistent gold potential in "Warped Muffin Tin" (WMT) form was computed. As a modell for the electron-electron interaction the effective local single-particle-potential in the context of the "Local Density Approximation" (LDA) with relativistic adjustments for the exchange-term of MacDonald and Vosko (1979) was used. On the basis of the energy spectrum, the density of states, and the anisotropy of the fermi-surface the approximations of WMT and DFF/LDA are discussed. The most essential result is, that with the selfconsistent potential there is in the energy-scale a movement of the occupied d-bands slightly upwards and a broadening of the d-bandwidth, in contrast to some experiments. Neddermeyer (1981) suggested a drastic upshift of the 7. band - for that proposal there is no evidence in this work. Because in this calculation exchange- and correlation-potentials are free from adjustable parameters, the author guesses, that in the difference between theory and experiment we have reached the limit of the local approximation (LDA). This publication is 99% identical with the PhD-thesis of the author at LMU Munich in March 1984. Minor add-ons are given in brackets [...]. A new appendix from 2012 adds some informations from the assets of the author and discusses some interesting newer PhD-theses about Copper and Gold, done at the Institut of Theoretical Solid State Physics (Prof. H. Bross) at LMU Munich.