Density functional theory study of hydrogen bonding in ionic molecular materials

Crystal structures are usually described in geometric terms. However, it is the energetics of intermolecular interactions that determine the chemical and physical properties of molecular materials. 1 In this paper, we use density functional theory (DFT) in combination with numerical basis sets to analyze the hydrogen bonding interactions in a family of novel ionic molecular materials. We find that the calculated binding energies are consistent with those of other ionic hydrogen bonded systems. We also examine electron density distributions for the systems of interest to gain insight into the nature of the hydrogen bonding interaction and investigate the effects of different aspects of the crystal field on the geometry of the hydrogen bond.