Structural chemistry of extended defects

Studies on the characterization of extended defects are reviewed under the following section headings: structures based on crystallographic shear, including crystallographic shear and shear vectors, one-dimensional crystallographic shear (shear in molybdenum and tungsten trioxides and rutile), two-dimensional crystallographic shear, and disordered crystallographic shear; and, the fluorite-related structures, including the relationship between the fluorite and other structures ( alpha -UO/sub 3/, CaF/sub 2/, La/sub 2/O /sub 3/, and Sm/sub2/O/sub 3/), the fluorite-related homologous series, and disordered fluorite-related phases. (120 references) (JGB)