Through Hydrogen-Bond Vibrational Coupling in Hydrogen-Bonding Chains of 4-Pyridones with Implications for Peptide Amide I Absorptions:  Density Functional Theory Compared with Transition Dipole Coupling

The effects of hydration on the ground-state structural stability and excited-state hydrogen-bonding dynamics of 2′-deoxyguanosine 5′-monophosphate (dGMP) carrying different negative charges were investigated with B3LYP/6–31+G(d,p) using density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods, respectively. Particularly, we not only considered the solvent effects by the polarizible continuum model (PCM), but also the first solvation shell was included explicitly. We demonstrated that the intramolecular hydrogen bond O2–H1···O3 will be weakened with the strengthening of the hydration. From the view of bond length, we can make a valid presumption that the site of negative charge will be the more preferable site of the hydration, and the preferable site may be changed because of the presence of other hydrogen bonds. Furthermore, we found that the first solvation shell had very little effect on the geometric structures except for the hydrogen bond P–O5···H5. By comparing the excitation energies, one important finding is that the changes in different electronic states are not obvious with the increase in n value when considering the PCM. Another finding is that the average interactions of hydrogen bonds may be strengthened with an increase of negative charge because of a decrease in excitation energies.

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Adsorption of atmospheric gas molecules (NH3, H2S, CO, H2, CH4, NO, NO2, C6H6 and C3H6O) on two-dimensional polyimide with hydrogen bonding: a first-principles study

New Journal of Chemistry ◽

10.1039/d0nj06013e ◽

2021 ◽

Vol 45 (11) ◽

pp. 5240-5251

Author(s):

Sujing Yu ◽

Dongzhi Zhang ◽

Wenjing Pan ◽

Jingbin Zeng

Keyword(s):

Density Functional Theory ◽

Hydrogen Bond ◽

Hydrogen Bonding ◽

First Principles ◽

Density Functional ◽

Two Dimensional ◽

Functional Theory ◽

First Principles Study ◽

Gas Molecules

In this study, we investigated the effects of hydrogen bond acceptors on the surface of two-dimensional polyimide towards NH3, H2S, CO, H2, CH4, NO, NO2, C6H6 and C3H6O gas molecules through first-principles study based on density functional theory.

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Computational Evaluation of Intermolecular Interaction in Poly(Styrene-Maleic Acid)-Water Complexes Using Density Functional Theory

Indonesian Journal of Chemistry ◽

10.22146/ijc.67961 ◽

2021 ◽

Vol 21 (6) ◽

pp. 1537

Author(s):

Daru Seto Bagus Anugrah ◽

Laura Virdy Darmalim ◽

Permono Adi Putro ◽

Liana Dewi Nuratikah ◽

Nurwarrohman Andre Sasongko ◽

...

Keyword(s):

Density Functional Theory ◽

Hydrogen Bond ◽

Hydrogen Bonding ◽

Molecular Orbital ◽

Maleic Acid ◽

Density Functional ◽

Basis Set ◽

Water Molecules ◽

Functional Theory ◽

High Hydrogen

The high application of Poly(styrene-maleic acid) (PSMA) in an aqueous environment, such as biomedical purposes, makes the interaction between PSMA and water molecules interesting to be investigated. This study evaluated the conformation, the hydrogen bond network, and the stabilities of all the possible intermolecular interactions between PSMA with water (PSMA−(H2O)n, n = 1–5). All calculations were executed using the density functional theory (DFT) method at B3LYP functional and the 6–311G** basis set. The energy interaction of PSMA–(H2O)5 complex was –56.66 kcal/mol, which is classified as high hydrogen bond interaction. The Highest Occupied Molecular Orbital (HOMO) – Lowest Unoccupied Molecular Orbital (LUMO) energy gap decreased with the rise in the number of H2O molecules, representing a more reactive complex. The strongest hydrogen bonding in PSMA–(H2O)5 wasformed through the interaction on O72···O17–H49 with stabilizing energy of 50.32 kcal/mol, that analyzed by natural bond orbital (NBO) theory. The quantum theory atoms in molecules (QTAIM) analysis showed that the hydrogen bonding (EHB) value on O72···O17–H49 was –14.95 kcal/mol. All computational data revealed that PSMA had moderate to high interaction with water molecules that indicated the water molecules were easily transported and kept in the PSMA matrix.

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Time-dependent density functional theory study on the electronic excited-state hydrogen bonding dynamics of BHC-nicotinamide in MeOH solution

Canadian Journal of Chemistry ◽

10.1139/cjc-2012-0393 ◽

2013 ◽

Vol 91 (4) ◽

pp. 248-254 ◽

Cited By ~ 1

Author(s):

Jinling Cheng ◽

Di Liu

Keyword(s):

Density Functional Theory ◽

Hydrogen Bond ◽

Hydrogen Bonding ◽

Excited State ◽

Ground State ◽

Density Functional ◽

Time Dependent ◽

Functional Theory ◽

Hydrogen Bonding Dynamics ◽

Hydrogen Bond Strengthening

The density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods were performed to investigate the electronic excited-state hydrogen bonding dynamics of the hydrogenbonded complex formed by BHC-nicotinamide (BHCN) and methanol (MeOH). The ground-state geometry optimizations, electronic transition energies, corresponding oscillation strengths of the low-lying electronically excited states, and the optimized S1 excited-state geometry for the isolated BHCN and MeOH monomers, the hydrogen-bonded BHCN–MeOH dimers, and BHCN–2MeOH trimer complexes have been calculated by using the DFT and TDDFT methods, respectively. We have demonstrated that the intermolecular hydrogen bond C10=O14···H40−O39−Me is weaker than C16=O17···H46−O45−Me in the hydrogen-bonded dimers and trimer no matter whether in the ground state or the excited state. In addition, our results are consistent with the relationship between the electronic spectral shifts and excited-state hydrogen bonding dynamics: hydrogen bond strengthening can induce the relative electronic spectra redshift, whereas a blueshift will be induced. In addition, we focused our attention on the frontier molecular orbital and the results could reasonably explain the hydrogen bond strengthening or weakening mechanism.

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Study on the interaction between catechin and cholesterol by the density functional theory

Open Chemistry ◽

10.1515/chem-2020-0038 ◽

2020 ◽

Vol 18 (1) ◽

pp. 357-368

Author(s):

Kaiwen Zheng ◽

Kai Guo ◽

Jing Xu ◽

Wei Liu ◽

Junlang Chen ◽

...

Keyword(s):

Density Functional Theory ◽

Hydrogen Bond ◽

Charge Transfer ◽

Density Functional ◽

Antioxidant Properties ◽

Micelle Formation ◽

Aromatic Rings ◽

Hydrogen Bond Interaction ◽

Functional Theory ◽

The Density Functional Theory

AbstractCatechin – a natural polyphenol substance – has excellent antioxidant properties for the treatment of diseases, especially for cholesterol lowering. Catechin can reduce cholesterol content in micelles by forming insoluble precipitation with cholesterol, thereby reducing the absorption of cholesterol in the intestine. In this study, to better understand the molecular mechanism of catechin and cholesterol, we studied the interaction between typical catechins and cholesterol by the density functional theory. Results show that the adsorption energies between the four catechins and cholesterol are obviously stronger than that of cholesterol themselves, indicating that catechin has an advantage in reducing cholesterol micelle formation. Moreover, it is found that the molecular interactions of the complexes are mainly due to charge transfer of the aromatic rings of the catechins as well as the hydrogen bond interactions. Unlike the intuitive understanding of a complex formed by hydrogen bond interaction, which is positively correlated with the number of hydrogen bonds, the most stable complexes (epicatechin–cholesterol or epigallocatechin–cholesterol) have only one but stronger hydrogen bond, due to charge transfer of the aromatic rings of catechins.

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