Electronic properties of transition-metal oxides—I

The distortions from cubic symmetry which occur in certain transition-metal oxides, particularly those with the spinel structure, are discussed in terms of crystal (ligand) field theory. It is shown that many such distortions, including all the large ones, are related in a simple fashion to the electronic configuration of the metal ion and may be considered to arise as a consequence of a Jahn-Teller type of distortion.