STRUCTURE REFINEMENTS FOR SOME PLATINUM METAL MONOSILICIDES

The crystal structures of platinum metal monosilicides were refined fr om powder diffraction data using the Rietveld method. The compounds st udied were the FeSi-type structure RuSi, OsSi and RhSi, and the MnP-ty pe structure RhSi, IrSi, PdSi and PtSi. The structure of the monoclini c form of RhSi, space group P2(1)/c, was also refined. The only CsCl-t ype structure observed was that of RuSi, which was obtained together w ith the FeSi-type polymorph. Atomic coordinates refined for PdSi, PtSi and FeSi-type RhSi are in good agreement with existing single-crystal data.