The metal-versus-semiconductor behavior of ruthenium pyrochloresA 2 Ru 2 O 7-y was examined by calculating their electronic band structures. This behavior is explained in terms of the Mott-Hubbard mechanism of electron localization. The width of thet 2g -block bands ofA 2 Ru 2 O 7-y increases with increasing Ru-O-Ru bond angle, and the Ru-O-Ru angle increases with increasing size of theAcation. There is a good linear relationship between the ionic radius of theAcation and the Ru-O-Ru bond angle. This relationship makes it possible to calculate the amount of the O′ atom vacancy based on the observed Ru-O-Ru angle in Tl 2 Ru 2 O 7-y .
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry