Abstract: The dihydrogen bonds B—H…H—X and traditional Hbonds N—H…X and X—H…X (X=F,Cl,O) between B₃N₃H₆ and each of HF, HCl or H₂O were theoretically studied by use of the ab initio quantum mechanics method (MP2). We found that the action of the dihydrogen bond made the BH and HX bonds redshifted, and that the formation of the traditional Hbonds made the NH and HX bonds redshifted. The topological properties of the complexes show that these intermolecular interactions were indeed Hbonds. The natural bond orbital analysis shows that these Hbonds can be interpreted by the theory of hypercon jugation and rehybridization.

Key words: dihydrogen bond, redshifted Hbond, blueshifted Hbond, hyperconjugation and rehybridization