The use of a point polarizable dipole in intermolecular potentials for water

The total dipole moment of a pair of isolated water molecules that employ a point polarizable dipole is compared with the total dipole moment obtained from MP4 calculations for the same intermolecular orientation and distance. At all reasonable intermolecular distances, the point dipole models give total dipole moments that are generally in very good agreement with MP4. This suggests that the point polarizable dipole approximation for water is reasonable and that the high dipole moments obtained frequently in molecular simulations of polarizable water must be attributed to something other than the inadequacy of the point dipole approximation.