Sound velocity and interparticle interaction in liquid rare-earth metals

The effect of the position and depth of the first minimum in the pair-interaction potential in liquid rare-earth metals (REM) on the frequency of the collective atomic vibrations is analyzed at small wave numbers and sound-propagation velocities. It is assumed that the depth of the first minimum in the interatomic-interaction potential decreases in a series of REM with increasing atomic number. Data on the position of the repulsive branch of the interparticle potential of the REM are cited.