Calculation of Coulombic energy for molecular crystals

Abstract

The first Bertaut series has been examined for practical application to evaluating coulombic contribution to lattice energy in molecular crystals; especially with Templeton's correction, its use seems to be quite advantageous because of its simplicity and does not seem to involve a longer computing time than other methods. For rigid molecules, a scheme of obtaining first and second derivatives of coulombic energy with respect to molecular rotation or translation is shown; this scheme can be easily applied to packing energy minimization and also to constrained refinement of crystal structures.