Probing the structures, binding energies, and spin-spin coupling constants of halogen-bonded Azine:ClF complexes

Abstract

Ab initio MP2/aug’-cc-pVTZ calculations were performed to determine the structures, binding energies, and charge-transfer energies of azine:ClF complexes. Binding energies and charge-transfer energies exhibit excellent correlations with the N-Cl distance, decreasing as the number of N atoms increases. EOM-CCSD spin-spin coupling constants 1xJ(N-Cl) do not correlate well with the N-Cl distance, although patterns emerge for each subgroup of complexes that have the same number of nitrogen atoms in the ring. The average value of the coupling constants for each subgroup exhibits an excellent correlation with the average distance, and illustrates the changing nature of the halogen bond.