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

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-C6H4Cl2)/p-dibromobenzene (1,4-C6H4Br2) molecular system has been used to illustrate the theoretical treatments.