Cation sublattice and coordination polyhedra in ABO(4) type of structures

The common features of the ABO(4) type of structures are reviewed and discussed. A preliminary statistical study of the distribution of the space group for these compounds is proposed and the similarities and differences among the structure types are discussed. Using the recently proposed approach for structural study (L. E. Depero and L. Sangaletti, J.Solid State Chem. 119, 428 (1995)), the cation sublattices of these structures are compared and described as a continuous transformation from the space group no. 216, in which the coordination number of the cation is 12, to the rutile and the alpha-PbO2 structures, where the coordination number is 6. In this approach, the phase transformation of the polymorphic phases, largely present in this family, can be understood in terms of changes in the cation sublattice. (C) 1997 Academic Press.