Temperature-Dependent Dispersion Coefficients of Alkali Metals Using Equation of State

Document Type : Research Paper


In this study, a temperature-dependent of the dispersion coefficients is calculated from equation state.
The Lennard-Jones LJ (12-6-3) effective pair potential function and simple thermodynamic argument
with the input PVT data of liquid metals are used to calculate the dispersion coefficients. The dispersion
coefficients ( , , ) 3 6 12 C C C are found to be a linear function of 1/T1+α , where T is the temperature and α
is a constant and has different values for different dispersion coefficients. The law of corresponding states
based on the reduced dispersion coefficients and reduced temperature is used to verify the validity of a LJ
(12-6-3) potential function in describing the dispersion coefficients. By applying the dispersion coefficients
of alkali metals and potential function plots, the values of molecular parameters (å , ó , and, m r ) have been
obtained. The LJ (12-6-3) potential function conclusively predicts the best dispersion coefficients of the
three alkali metals (K, Rb, and Cs).