Sound Velocity and its Temperature Coefficient of Liquid La, Ce and Pr

The sound velocity and its temperature coefficient in liquid La, Ce and Pr have been estimated using an improved Rosenfeld's approach. The temperature coefficient of the sound velocity in liquid Ce is positive, which is quite different from that of La and Pr. To reproduce the positive temperature coefficient of the sound velocity in liquid Ce, it is necessary to take into account the effect caused by electrons. The present calculations based on Ascarelli's approach suggest an increase in derealization of the 4f electrons with temperature in the liquid state of Ce. This is consistent with the results given by McAlister and Crozier