Simple and perovskite oxides of transition-metals: Why some are metallic, while most are insulating

• Published in: Journal of solid state chemistry Vol. 90; no. 1; pp. 168 - 172
• Main Authors: Torrance, Jerry B., Lacorro, Philippe, Asavaroengchai, Chinnarong, Metzger, Robert M.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 1991; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electrical and thermal conduction in crystalline metals and alloys; Electronic conduction in metals and alloys; Electronic transport in condensed matter; Exact sciences and technology; Physics; Conductivity; Ionization potential; Transition metal Oxides; Electronic structure; Perovskite type compound; Energy level
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/0022-4596(91)90182-H

Some 76 simple and perovskite transition-metal oxides are classified as “metals,” “insulators,” and those exhibiting metal-insulator transitions. Using the framework of Zaanen, Sawatzky, and Allen and a simple ionic model to estimate the two relevant energies ( Δ 0 and U′ 0), we can find boundaries which separate the insulating oxides from two types of metals: low Δ 0 metals and low U′ 0 metals. In addition, compounds with metal-insulator transitions are found to be on (or near) these boundaries. It is concluded that the large differences in conductivity behavior of oxides are largely due to differences in the ionization potentials of the transition metal cations.