Magnetism and transport properties of HfMSi (M = PT, Pd) and HfRh1-xPdxSi

The crystallographic, electric, and magnetic properties of the new intermetallic compounds HfMSi (M = Pt or Pd) and the superconductivity of HfRh1-xPdxSi were studied. The crystal structure of HfPtSi and HfPdSi could be refined assuming an orthorhombic structure (space group Pnma) and lattice constants of a = 0.6549 nm, b = 0.3883 nm, and c = 0.7505 nm for HfPtSi and a = 0.6570 nm, b = 0.3874 nm, and c = 0.7565 nm for HfPdSi. Both compounds are metallic and show diamagnetic behavior below 300 K. A small effective electron mass is thought to be a reason for the diamagnetism of HfMSi (M = Pt or Pd). In the HfRh1-xPdxSi system, the superconductivity of HfRhSi (T-c = 2.2 K) is suppressed by replacing Ph by Pd. The Pd content dependence of the Pauli paramagnetic susceptibility suggests that reduction of the density of states at the Fermi level is a possible cause of the suppression of superconductivity in the HfRh1-xPdxSi system. (C) 2000 Published by Elsevier Science S.A. AU rights reserved.