Illustration 1 Transition Metal Oxides with Vertex-Sharing Octahedra

1 Illustration 1 Transition Metal Oxides with Vertex-Sharing Octahedra 

ReOs has the octahedral framework of the SrTiOs structure minus the 12-coordinate atom in the center of the unit cell. However, the orbitals on this atom ate of such high energy (Sr electron configuration = 4s 4p 5s ) that they do not hybridize with the Ti 3d-02p bands. In the perovskite stmcture, this atom simply provides electrons to the system that can occupy the valence or conduction bands. Hence, there is little change to the band dispersion directly resulting from the presence of the A cation. 

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