225

117A

117A

PHYSICAL REVIEW B

V.49, No.5

(1994)

P.3049-3060

Compressed solids,Equation of state,Internal energy

We derive a universal equation of state for compressed solids,based on thermodynamic arguments applied to virial expansions of E (p,T) and p(p,T), of the from p(v /v0)2= A0 + A1 (p/p0)+ A2(p/p0)2. The thermal pressure is included from the beginning,and the only essential approximation is the truncation of expansions, which is justified by molecular arguments. Agreements with experiment is very good for a wide range of materials, including quantum solids, noble-gas and polar-gas solids, metals, ionic compounds,and hydrocarbons. A separate assumption gives the temperature dependence of the parameters as A1(T)=A + biT -ci T in T, for> 0 D. The usual behavior of the Gruneisen number as a function of temperature and density is accounted for in a simple way by these results.

1376/08

Shahsvary

GN114073