Electric Field Gradients at the In Site in Au-In Compounds

Abstract

The quadrupole interaction in Au-In compounds of different stoichiometrics was studied with the perturbed angular correlation technique. The electric field gradients at 11 : Cd probes were measured and the temperature dependences of the quadrupole frequencies were determined. A new high temperature phase of Auln above 630 K and a new metastable modification of Au 7 In 3 were found.

ZrAg and Zr2Ag phases studiedby perturbed angular correlation with 181Ta probes

“…The corresponding quadrupole frequency at room temperature is ν Q = 798(5) MHz. The shape of the spectrum points to a texture of the sample similar to that observed for many Hf and Zr intermetallic compounds [2,3,5,10,11]. The value of the quadrupole frequency obtained and the corresponding EFG (see Table 1) are close to the values for the isostructural HfAg compound [10], reflecting the chemical similarity of Hf and Zr and the similar lattice constants of both compounds.…”

“…A linear decrease of the EFG with increasing temperature, observed for ZrAg, was also found in isostructural HfAg [10] and some other metallic systems such as Cu 8 Hf 3 , Cu 8 Zr 3 [2], Al 3 Hf 2 [3], Al 3 Zr 2 [14], or Hf 2 Ni and Zr 2 Ni [15]. The temperature changes of V zz measured in Zr 2 Ag are very weak and the shape of the V zz (T) curve is unusual, similarly as in Hf 2 Ag [10].…”