Impurity Quadrupole Interaction in Light Rare Earth Metals: 111Cd in La, Pr and Nd

Abstract

The nuclear quadrupole interaction of dilute light rare earth (RE) metals La, Pr and Nd by time differential perturbed angular correlation measurements. The quadrupole frequency νQ has been determined in Pr as a function of temperature and pressure, in Nd as a function of temperature, and in La at 19 K. The pressure dependence of νQ of 111Cd in Pr ((d In νQ/d P)290 K = + 2.7 (2.3) · 10-3 Kbar-1) is a factor of 3 - 4 weaker than in the heavy RE metals Gd to Er. At the same time the temperature dependence of νQ in the light RE is up to a factor of 3 stronger than in the heavy RE. Between 300 K and 900 K. the quadrupole frequency is a linear function of temperature with the same slope (d In νQ/dT)290 k = - 8.4(2) · 10-4 K-1 both in Pr and Nd. Between 25 K and 300 K the decrease is stronger than linear, and more pronounced in Pr than in Nd. The temperature coefficient (d In νQ/dT)290 k is found to decrease linearly with the RE atomic number across both the series of the fight and the heavy RE metals.