Description
Theoretical and numerical details of an optimized LCAO (linear combination of atomic orbitals) method for the calculation of self-consistent bandstructures are given together with a variety of examples. The method will be a valuable tool both for researchers engaged in calculations and for scientists looking for numerical results of self-consistent bandstructure calculations. The presentation starts with an introduction to the modern many-body theory of electronic bandstructure. The essentials of the representation with a non-orthogonal basis and the usual tight-binding variants are critically reviewed. A variational approach to the optimization of atom-like basis orbitals is described together with an SCF procedure for band calculations. Complete numerical and graphic results for all elementary metals from lithium to zinc are given. Content.- 1. Introduotion.- 2. The LCAO formalism.- 3. Optimization of the basis.- 4. Wannier funotions.- 5. The local basis representations of the electron density.- 6. Simplex methods for k-epaos integrations in d dimensions.- 7.. Potential oonstruotion and iteration.- Appendix 1. Spherical harmonics and their transformations.- Appendix 2. Some useful theorems on basis function expansions.- Appendix 3. Results of DFT-LCAO band structure calculations for element metals.- References.
