A SAPT Study of the H2O X2 Complexes; X = H, N and F

Abstract

Abstract-The interaction energy of the H2O· · · X2 complexes, with X = H, N and F has been analyzed by using the SAPT (Symmetry Adapted Perturbation Theory) methodology. The decomposition of the interaction energy into distinct physical components is a unique feature of SAPT which distinguishes this method from the supermolecular approach. In SAPT, the interaction energy is expressed as a sum of perturbative corrections, each correction resulting from different physical effect. SAPT results show that the above systems possess quite different features; while the complex with hydrogen is dominated by dispersion, a subtle balance of dispersion and induction is effective in stabilizing the complex H2O· · · N2, and induction (due to the strong electronegativity of fluorine) is the leading term in the pre-reactive vdW complex H2O· · · F2.