Magnetic Ordering in Lithium-Transition Metal Oxides with Ordered Rocksalt Structures

摘要

A better understanding of the nature and mechanisms of superexchange is sought by studying magnetic ordering in compounds isotypic with alpha-NaFeO2. Exchange, superexchange, and Weiss molecular field theory are reviewed. The Heisenberg-Dirac-Van Vleck Hamiltonian is derived by an intuitive method. The historic development of superexchange in terms of quantitative theory and qualitative rules is considered. The Weiss molecular field theory is used to compute the exchange parameters. Its advantages, limitations and predictions are stated and the several expressions employed are developed. The crystal chemistry and some physical properties of ordered rocksalts isotypic with alpha-NaFeO2 are analyzed. (Author)