ELECTRIC QUADRUPOLE INTERACTION AT TA-181 PROBES IN HEXAGONAL TINI3-TYPE COMPOUNDS

The perturbed angular correlation technique was applied to study the e lectric field gradient (EFG) in TiNi,-type compounds. HfPd3, Zr0.98Hf0 .02Pd3 and Ti0.98Hf0.02Pd3 samples were neutron irradiated in order to produce Ta-181 probes. The perturbed angular correlation measurements performed in the temperature range 45 K-11O0 K demonstrated the exist ence of two axially symmetric EFGs in each of the investigated compoun ds related to the 2(a) and 2(c) probe sites in the DO24 structure. The temperature dependence of the quadrupole frequencies exhibits differe nt slope parameters for each of the observed frequencies.