Analysis of hydrogen bond energies and hydrogen bonded networks in water clusters (H2O)_(20) and (H2O)_(25) using the charge-transfer and dispersion terms

摘要

The hydrogen bonds and their networks in the water clusters (H2O)_(20) and (H2O)_(25) are characterized using the charge-transfer (E_(CT)~(W_a,W_d)) and dispersion [E_(Disp)~(W_a,W_d)) terms for every pair of water molecules (W_a, W_d) in the clusters. The terms are evaluated by the perturbation theory based on the ab initio locally projected molecular orbitals (LPMO PT) developed by the present author. The relative binding energies among the isomers evaluated by the LPMO PT agree with those of the high level ab initio wave function based theories.