Dynamical Mean Field Theory for d Electrons on Cubic Lattices with Realistic Electron Hopping and Interaction

Abstract

The noncrossing approximation (NCA) for solving an impurity problem of interacting electrons is applied to the dynamical mean field theory for a d -electron system on cubic lattices. Anisotropy in the hopping integrals as well as intraatomic Coulomb interactions and the crystalline field splitting of d orbitals are fully considered. Single-particle excitation spectra are calculated for various occupations of the d band and discussed with reference to the multiplet spectra obtained in the NCA calculation and the k -dependent spectra. Differences in the results of the NCA and the iterative perturbation theory are discussed.