From all-atom vision to molecular pairwise-interactions: the mean-field approach in molecular alloys

Abstract The pairwise-interaction model for molecular alloys has been improved by using all-atom potential functions. Both descriptions have been correlated under a more general approach, the mean-field. Expressions for the excess internal energy have been obtained. Two sources of non-thermodynamical regularity arose: the differences in the geometry and chemical nature of the molecules and the non-transferability of the interaction potentials from pure components to alloys. The p -dichlorobenzene (1,4-C 6 H 4 Cl 2 )/ p -dibromobenzene (1,4-C 6 H 4 Br 2 ) molecular system has been used to illustrate the theoretical treatments.