• D-Patterson;
  • intermetallic compound;
  • Friedel differences

The X-ray single-crystal diffraction intensities of the intermetallic compound TiGePt were analysed. These showed beyond doubt that the crystal structure is non-centrosymmetric. The analysis revolves around the resonant-scattering contribution to differences in intensity between Friedel opposites hkl and inline image. The following techniques were used: Rmerge factors on the average (A) and difference (D) of Friedel opposites; statistical estimates of the resonant-scattering contribution to Friedel opposites; plots of 2Aobs against 2Amodel and of Dobs against Dmodel; the antisymmetric D-Patterson function. Moreover it was possible to show that a non-standard atomic model was unnecessary to describe TiGePt. Two data sets are compared. That measured with Ag Kα radiation at 295 K to a resolution of 1.25 Å−1 is less conclusive than the one measured with Mo Kα radiation at 100 K to the lower resolution of 0.93 Å−1. This result is probably due to the fact that the resonant scattering of Pt is larger for Mo Kα than for AgKα radiation.