An approximate formula for the intermolecular Pauli repulsion between closed shell molecules. II. Application to the effective fragment potential method

The accuracy and efficiency of an approximate formula for the intermolecular Pauli repulsion between closed shell molecules, derived earlier [Mol. Phys. 89, 1313 (1996)], is demonstrated for dimers of H2O, CH3OH, CH2Cl2, CH3CN, (CH3)2CO, and (CH3)2SO. The energy derivative with respect to a Cartesian coordinate and rigid rotation about the center-of-mass (torques) are presented. The Pauli repulsion energy term is then combined with the Coulomb and classical induction energy terms of the effective fragment potential method [J. Chem. Phys. 105, 1968, 11081 (1996)] to give a general intermolecular interaction potential. This potential is applied to water and methanol clusters.