M. Marszalek et al., ELECTRIC-FIELD GRADIENT AND ITS TEMPERATURE-VARIATION AT A TA-181 PROBE IN ZR2FE AND ZR2CO INTERMETALLIC COMPOUNDS, Journal of alloys and compounds, 219, 1995, pp. 124-127
In this paper we report a time differential perturbed angular correlat
ion study of electric field gradients and their temperature variation
in Zr2T (T=Fe,Co) intermetallic compounds (C16 crystallographic struct
ure). Measurements were performed at a Ta-181 radioactive probe in the
temperature range 20 K-1173 K. In both samples only one strong asymme
tric quadrupole interaction was observed, consistently with one possib
le crystallographic position of the probe atom in the studied structur
e. The quadrupole coupling constant is equal to 1039(8) MHz with asymm
etry parameter eta=0.82 and 889(7) MHz with eta=1 at room temperature
for Zr2Fe and Zr2Co respectively. In the investigated temperature rang
e a linear dependence of electric field gradient was observed in contr
ast to the T-3/2 dependence found in most intermetallic compounds and
non-cubic metals.