Modeling the Electronic and Structural Properties of Transition-Metal Oxides

First principles calculations are presented for the structural, cohesive, and electronic properties of technologically important transition-metal oxides. Calculations were performed within the local-density approximation using soft-core ab initio pseudopotentials and a plane-wave basis. Results are presented for TiO_2, RuO _2, and the Ru_{rm x}Ti_{rm 1-x} O_2 mixed oxide system. Ground state properties such as cohesive energies, lattice constants, elastic properties, pseudo-valence charge densities, Fermi surfaces, transport properties, defect energies, and valence band density of states were found to be in good agreement with experimental measurements. This study was the first to address the applicability of the local-density approximation in describing the optical properties of an early transition -metal oxide as well as the first realistic calculations for a transition-metal dopant in a ceramic oxide. This study suggests that material properties for early as well as late transition-metal oxides are well reproduced by pseudopotentials constructed within the local-density approximation.