Physical nature of interactions in charge-inverted hydrogen bonds

► Hybrid variational-perturbation method is utilized to decompose the interaction energy of charge-inverted hydrogen bonds. ► The electrostatic and delocalization energy terms are the most stabilizing components. ► The electrostatic multipole term is the only one that closely reproduces the MP2 minimum conformation. ► If CIHB is linear then the delocalization energy term prevails.