Palladium Site Ordering and the Occurrence of Superconductivity in Bi₂Pd₃Se₂−xSx


R Weihrich, S F Matar, I Anusca, F Pielnhofer, P Peter, F Bachhuber, and Volker Eyert

Journal of Solid State Chemistry 184, no. 4 (April 1, 2011): 797–804

The crystallographic and electronic structures of compounds related to parkerite (Bi₂Ni₃S₂) are investigated with respect to the recently reported occurrence (Bi₂Pd₃Se₂) and absence (Bi₂Pd₃S₂) of superconductivity. Similarities and differences of the crystal structures are discussed within the series of solid solutions Bi₂Pd₃S₂-xSex from powder and single crystal diffraction data. From crystal structure refinements, the question of different structures and settings of parkerite is discussed. Similar and different 2D and 3D partial Pd–Ch (Ch=S, Se) structures are related to half antiperovskite ordering schemes. To investigate the relation of low dimensional structures and the occurrence of super- conductivity, electronic structures are analyzed by scalar-relativistic DFT calculations, including site projected DOS, ECOV and Fermi surfaces.