A polarizable dipole-dipole interaction model for evaluation of the interaction energies for N-H···O=C and C-H···O=C hydrogen-bonded complexes.
In this article, a polarizable dipole-dipole interaction model is established to estimate the equilibrium hydrogen bond distances and the interaction energies for hydrogen-bonded complexes containing peptide amides and nucleic acid bases. We regard the chemical bonds N-H, C=O, and C-H as bond dipoles. The magnitude of the bond dipole moment varies according to its environment. We apply this polarizable dipole-dipole interaction model to a series of hydrogen-bonded complexes containing the N-H···O=C and C-H···O=C hydrogen bonds, such as simple amide-amide dimers, base-base dimers, peptide-base dimers, and β-sheet models. We find that a simple two-term function, only containing the permanent dipole-dipole interactions and the van der Waals interactions, can produce the equilibrium hydrogen bond distances compared favorably with those produced by the MP2/6-31G(d) method, whereas the high-quality counterpoise-corrected (CP-corrected) MP2/aug-cc-pVTZ interaction energies for the hydrogen-bonded complexes can be well-reproduced by a four-term function which involves the permanent dipole-dipole interactions, the van der Waals interactions, the polarization contributions, and a corrected term. Based on the calculation results obtained from this polarizable dipole-dipole interaction model, the natures of the hydrogen bonding interactions in these hydrogen-bonded complexes are further discussed.
Department of Chemistry, Liaoning Normal University, Dalian, 116029, People's Republic of China.
Shu-Shi
SS
Li
Cui-Ying
CY
Huang
Jiao-Jiao
JJ
Hao
Chang-Sheng
CS
Wang
D006860:Hydrogen Bonding; D008956:Models, Chemical; D008958:Models, Molecular; D009696:Nucleic Acids / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D013816:Thermodynamics
D009696:Nucleic Acids; D010455:Peptides
dipole-dipole interaction; hydrogen bond; induced bond dipole moment; interaction energy; permanent bond dipole moment; polarization