On the representation of the electric charge distribution in ethane for calculations of the molecular quadrupole moment and intermolecular electrostatic energy
Abstract
It is shown that a simple atom‐site monopole model is inferior to one which includes higher‐order local multipoles to represent the intramolecular charge distribution of ethane. Unlike the latter model, the local monopole representation predicts the wrong sign for the molecular quadrupole moment and gives a repulsive rather than an attractive electrostatic interaction at typical intermolecular distances. In the local multipole model, the atom‐site dipoles give the largest contribution to both the molecular quadrupole moment and the intermolecular interaction.
Citation
J. Chem. Phys. 83, 348 (1985)