Phonon frequencies, elastic and Gruneisen constants of liquid chromium

Abstract

The potential function as formulated by Bretonnet and Deroache is used to evaluate the phonon frequencies, elastic and Gruneisen constants. The latter is also evaluated by a different method as well. The elastic constants are also calculated through Schofield's equations. All the results are found to be in agreement with each other. From the parameters used for the computation of the structure factor we obtain S(0), the structure factor in the long-wave limit and hence the compressibility from which the velocity of the sound is calculated. Assuming Ziman's theory that the structure factor peaks around 2κ_F, we find that the longitudinal phonon frequency maximum occurs at κ_F and from this value and sound velocity the maximum of the phonon frequency could be predicted. From the sum rules of frequency dependent structure factor the maximum value of ω_L(κ) is predicted. The maximum values so obtained by different methods are in satisfactory agreement with each other.