A DEBYE-GRUNEISEN THERMAL CORRECTION TO THE MURNAGHAN EQUATION OF STATE OF SOLIDS

By using the so-called ''universal'' zero-temperature equation of stat e of solids (EOS), proposed recently by Vinet et al., and a Debye-Grun eisen expression for the thermal pressure, an EOS for extended P-V-T c onditions is presented. This EOS is used to calculate the thermal expa nsion coefficient for 23 different metals, obtaining good agreement wi th experimental data. In addition, we calculate the temperature depend ence of the derivative of the bulk modulus (B) with pressure at zero p ressure (partial derivative B/partial derivative P\(tau) = n). This pa rameter is used as an input parameter in several EOS, such as the Murn aghan EOS in which it is assumed to be a constant, mainly due to a lac k of reliable experimental data about its temperature dependence. The temperature dependence of n obtained can be fitted well by aquadratic expression of the type n = A(0) + A(1)T + A(2)T(2). A table containing the fit coefficients is also presented. (C) 1998 Elsevier Science Ltd . All rights reserved.