Study of correlations for dihydrogen bonds by quantum-chemical calculations

An analysis of dihydrogen-bonding systems optimized in calculations employing B3LYP and MP2 methods shows the existence of correlations between geometrical parameters and H-bond energies. For the X–H⋯H–F systems there is evidence of the correlation between the covalent H–F donating bond length and the H⋯H distance, similarly as for the stronger O–H⋯O and N–H⋯O hydrogen bondings.