d(z2) orbital character of polyhedra in complex solid-state transition-metal compounds

摘要

In transition-metal compounds, the character of the d orbitals often plays an important role in the development and enhancement of novel physical and chemical properties. Density functional theory calculations of the electronic structures of various d(0)- and d(1)-complex transition-metal compounds consisting of either face-sharing octahedra, edge-sharing octahedra, or edge-sharing trigonal prismatic layers were performed to investigate the nature of their d orbitals. The d(z2) orbital of the transition metal was shown to make a significant contribution to the electronic structure near the Fermi level in nine different complex transition-metal compounds (oxides, nitrides, and sulfides), regardless of the type of polyhedral geometry and connectivity. The importance of controlling and designing the d(z2) orbital character of transition metals near the Fermi level was shown to be important in developing novel physical and chemical properties in complex transition-metal compounds.