Evaluation of classical potential functions for hydrogen bonding in 7-azaindole and 1-azacarbazole complexes

The accuracy of classical potential functions for representing the hydrogen bonding between 7-azaindole and 1-azacarbazole and various complexing partners is evaluated by comparison to ab initio calculations and experimental data in dilute solution. The potential functions utilize standard Lennard-Jones parameters along with charges derived from electrostatic potential fits to ab initio wavefunctions of the monomers. For the cases examined such classical potentials reproduce ab initio calculations and available experimental data on 1:1 complexes of 7-AI and 1-AC with various hydrogen-bonding partners to an accuracy of ±3.8 kJ/mol or ±13% without adjustment of parameters.