Halogen Bonds between Diiodotetrafluorobenzenes and Halide Anions: Theoretical Analysis

Abstract

The ωB97XD/aug-cc-pVTZ calculations were performed on complexes containing one or two diiodotetrafluorobenzene molecules and halide anions. These complexes are linked by a single halogen bond or by two such interactions, respectively. The corresponding calculations on complexes of iodopentafluorobenzene and iodobenzene with halide anions were also carried out for comparison. The properties of all interactions mentioned above are analyzed using results of DFT calculations that are supported by outcomes of the Quantum Theory of Atoms in Molecules approach. The decompositions of interaction energies were also performed for complexes of diiodotetrafluorobenzene, iodopentafluorobenzene, and iodobenzene species with halide anions. It was found that the electrostatic and orbital-orbital interaction energies are the most important attractive terms and that they contribute approximately equally to the total interaction energy for the complexes analyzed here. The searches through the Cambridge Structural Database were performed to find crystal structures containing similar arrangements of diiodotetrafluorobenzenes as those analyzed theoretically.