LUTETIUM AND OXYGEN DISPLACEMENTS IN ORTHORHOMBIC T'-TYPE LU2PDO4-DELTA

摘要

Lutetium palladium oxide, Lu2PdO4-delta, has been prepared in a multianvil apparatus at 60 kbar pressure and 1100 degrees C. It crystallizes in an orthorhombic T' (Nd2CuO4)-type structure with the space group Pbca (No. 61), a=5.479(1) Angstrom, b= 5.501(1) Angstrom, c = 11.579(2) Angstrom, V= 349.0 Angstrom(3), and Z= 4. Lutetium and oxygen displacements in the new phase create sixfold coordination for Lu, relieve the compressive stress on the Pd-O bonds resulting from the geometrical mismatch between the PdO2 and Lu2O2 layers, and reduce the electrostatic repulsion between oxygens. (C) 1997 Academic Press. [References: 22]