The TiPd2 compound studied by PAC with 181Ta and 111Cd probes

The intermetallic compound TiPd2 has been investigated with the perturbed angular correlation technique using radioactive Hf-181/Ta-181 and In-111/Cd-111 probes. The measurements confirmed an orthorhombic distortion of the C11(b) structure in the temperature range from 24 to 1023 K. However. the temperature dependence of the Cd-111 quadrupole parameters demonstrated that above 650 K the indium ions reach the lattice site of high symmetry characterized by an axially symmetric electric field gradient (EFG). The situation for the Hf-181/Ta-181 probes is more complex: we observed two electric field gradients, whose fractions interchange near 700 K, possibly due to Hf-181 probes switching their positions but still occupying a low-symmetry site. (C) 2004 Elsevier B.V. All rights reserved.