Figure 4.

Morokuma–Kitaura energy decomposition of the (A,B) H_OPT and (C,D) F_OPT geometries of G:C W:W Trans and G:G W:H Cis base pairs with neutral, N3-protonated and N7-protonated guanine. (E,F) Difference between different energy components of the H_OPT and (C,D) F_OPT systems are also shown. Abbreviations used here for different components of interaction energy are as follows, ES = electrostatic, EX = exchange repulsion, PL = polarization, CT = charge transfer, and MIX = higher-order coupling.