Ab initio interaction potential of methane and carbon dioxide: Calculation of second-virial coefficient

Document Type : Research Paper




An interaction potential at different orientation for the CH4 and CO2 complex was derived at the
B3LYP level of theory and 6-31+G* basis sets. The potential energy surface was computed on some
molecular geometries. The complete basis set limit of the interaction energies were fitted to wellknown
analytical functions. To determine the second virial coefficients B, U(r) is used to obtain the
model’s parameters over the range of temperatures of interest.