Directional Dependence of Hydrogen Bonds: a Density-based Energy Decomposition Analysis and Its Implications on Force Field Development.

摘要: One well-known shortcoming of widely used biomolecular force fields is the description directional dependence hydrogen bonding (HB). Here we aim to better understand origin this difficulty and thus provide some guidance for further field development. Our theoretical approaches center on a novel density-based energy decomposition analysis (DEDA) method (J. Chem. Phys. 2009, 131, 164112), in which frozen density variationally determined through constrained search. This unique most significant feature DEDA enables us find that interaction term key factor determining HB orientation, while sum polarization charge-transfer components shows very little dependence. new insight suggests current nonpolarizable describe not due lack explicit or terms. Using results as reference, furthe...