In silico prediction of drug solubility: 2: Free energy of solvation in pure melts

The free energy perturbation method is employed to study the free energy of solvation of a drug molecule in its pure drug melt, which is supposed to be considered the second step in predicting the solubility of drugs in water. The analysis reveals contradictory results, revealing that the Coulomb interactions are much weaker in pure drug systems, whereas the van der Waals interactions are extremely important and highly influence the interaction.