A DETAILED INVESTIGATION OF THE DYNAMIC AND THERMODYNAMIC PROPERTIES OF LIQUID GERMANIUM

Using Rao-Joardar's equation the potential energy of interaction in li quid germanium at a density of 46.5 nm-1 is derived. The potential fun ction shows a kink at 0.29 nm and an attractive minimum at 0.46 nm cor responding to the first and second nearest-neighbour distances. The va lues calculated by other methods is found to be in good agreement with the present values. The derivatives of the potential function are use d to calculate the phonon frequencies using Bhatia-Singh's (BS) method and also by that of Hubbard and Beeby (HB). The agreement between the two methods is fair. Using Bhatia-Singh's method the elastic constant s are calculated. They are also calculated through the use of velociti es in the long-wave limit as obtained from the equations of Takeno and Goda and are from the phonon frequencies as obtained from Hubbard and Beeby's equations. The elastic constants calculated by different meth ods are found to be in good agreement with each other. Using the third and second derivatives of the potential the Gruneisen constant gamma( g) is evaluated. It is also calculated through pressure and energy of the vibrations. The values obtained by different methods are intercons istent. An average value of 1.39 for gamma(g) is obtained. The Gruneis en constant is used to evaluate the pressure derivative of the diffusi on coefficient.