Interpretation of the Energy of Hydrogen Bonding; Permanent Multipole Contribution to the Energy of Ice as a Function of the Arrangement of Hydrogens

Abstract

A comprehensive calculation of the permanent multipole lattice energy of ice I, performed as part of a study of the orientational energy of ice and the nature of the hydrogen bond, has led to the following conclusions: (1) The energy for existing quantum‐mechanical models can be approximated with simple point‐charge models (Sec. VI.E). (2) The effects of several characteristics of the molecular charge distribution have been quantitatively determined (Sec. VI.D). (3) There is a variation of energy with the configuration of the hydrogens (Sec. VI.F). (4) There is little correlation between the energy variations and the polarity of the crystal (Sec. VI.C). (5) In a study of these energy variations, the slow convergence in the sums over both lattice points and multipole orders makes it necessary to include interactions beyond next‐nearest neighbors for lower‐order multipoles as well as interactions of higher than the quadrupole—quadrupole order (Sec. VI.B).