Pressure-volume-temperature relationship for diatomic solids based on inverted and non-inverted equations of state

721-725The pressure-volume-temperature (P-V-T) relationship using inverted and non-inverted equations of state (EOS) for diatomic solids such as NaCl, MgO and LiH has been studied. It is found that the inverted type EOS due to Roy and Roy [Physica B, 350 (2004) 1945.] yields close agreement with the results obtained from the non-inverted equations due to Rydberg [J Phys, 73 (1932) 376.], Shanker et al.[Physica B, 271 (1999) 158], Hama and Suito [J Phys, 8 (1996) 67.] for isothermal compressions as well as isothermal bulk modulus. The Roy - Roy inverted EOS has been found to have an additional advantage of predicting volumes for a solid at simultaneously elevated pressure and temperature. We have used this EOS to obtain P-V-T results for NaCl and MgO. The calculated values present close agreement with the experimental data