HYDROCARBON LONG-RANGE INTERACTION COEFFICIENTS FROM POINT CHARGE MODEL FORMULAS

Two-body interaction coefficientsC6 andd4 and the three-body coefficient γ3 are calculated for interactions between like species for a variety of hydrocarbons. Three different point charge models are employed and results are similar when Frost model Lewis set wavefunctions are used and in agreement with other literature values where available. We also consider simple Slater-Kirkwood type formulae for the coefficients and it turns out that very similar results to theab initio model values are found ford4. The formulae can also be used in conjunction with molecular fragment wavefunctions.