Competition of hydrogen, tetrel, and halogen bonds in COCl2-HOX (X=F, Cl, Br, I) complexes

The present study investigates the competition between hydrogen, halogen, and tetrel bonds from the interaction of COCl2 with HOX using quantum chemistry simulations at the MP2/aug-cc-pVTZ computational level, in which five configurations were optimized, including adducts I -V. Two hydrogen bonds, two halogen bonds, and two tetrel bonds were obtained for five forms of adducts. The compounds were investigated using spectroscopic, geometry, and energy properties. Adduct I complexes are more stable than others, and adduct V halogen bonded complexes are more stable than adduct II complexes. These results are in agreement with their NBO and AIM results. The stabilization energy of the XB complexes depends on the nature of both the Lewis acid and base. The stretching frequency of the O-H bond in adducts I, II, III, and IV displayed a redshift, and a blue shift was observed in adduct V. The results for the O-X bond showed a blue shift in adducts I and III and a red shift in adducts II, IV, and V. The nature and characteristics of three types of interactions are investigated via NBO analysis and atoms in molecules (AIM).

Automated summary

The competition between hydrogen, halogen, and tetrel bonds in the interaction between COCl2 and HOX was investigated using quantum chemistry simulations. Five configurations of adducts were optimized and spectroscopic, geometry, and energy properties were analyzed. The stability of adduct I complexes and adduct V halogen bonded complexes were found to be higher than others, which is consistent with their NBO and AIM results. The interaction energy of XB complexes depended on the nature of Lewis acid and base.