Thermodynamic properties of alkali metals from a statistically-based equation of state
M. Kiani, M. M. Alavianmehr, J. Moghadasi and S. Mousavi
It is the purpose of the present work to predict thermodynamic properties of alkali metals including lithium, sodium, potassium, rubidium, and cesium over a wide range of PVT space using a statistically-based equation of state (EOS). The EOS is that of Ihm-Song-Mason (ISM) EOS. The second virial coefficient, which plays a vital role in the EOS, is calculated from a corresponding states correlation with two scaling constants including latent heat of vaporization and molar density both at triple point. Further the second virial coefficient of lithium is calculated by using an accurate pair potential energy for singlet and triplet sates. The first quantum correction has been considered for calculating the second virial coefficient of lithium. Other two temperature-dependent parameters required by the ISM EOS are determined by the usage of Lennard-Jones (12–6) model potential. The calculated results are compared with literature data. The overall agreement between our results and literature values is remarkable.
Keywords: Alkali Metals, Equation of State, Thermodynamic Properties, Second Virial Coefficient, Corresponding States Principle, Pair Potential Energy