Session G28 - DMP: DEFECTS IN MATERIALS
Mixed session, Tuesday afternoon, March 21, 14:30
Empire Room, Fairmont Hotel
Perturbed angular correlations of gamma rays was used to detect lattice defects in quenched samples of B2-phase PdIn. Vacancies on both the Pd and In sublattices were detected with atomic-scale resolution through the quadrupole interactions they induce at 111In probe sites. With quenching temperature increasing in the range 550-1200 C, site fractions of signals from V/Pd/ and V/In/ defects first increased but then saturated above about 1000 C. Near the equiatomic composition, the site fractions were found to be roughly constant, implying that the high-temperature equilibrium defect in PdIn is the Schottky defect (a vacancy on each sublattice). The temperature dependence of the V/Pd/ defect concentration in the range 550-925 C was fitted to obtain a value of 1.3(1) eV for the formation enthalpy of a Schottky vacancy-pair.