• Title, Summary, Keyword: hydrogen bonding

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Hydrogen Bonding Analysis of Hydroxyl Groups in Glucose Aqueous Solutions by a Molecular Dynamics Simulation Study

  • Chen, Cong;Li, Wei Zhong;Song, Yong Chen;Weng, Lin Dong;Zhang, Ning
    • Bulletin of the Korean Chemical Society
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    • v.33 no.7
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    • pp.2238-2246
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    • 2012
  • Molecular dynamics simulations have been performed to investigate hydrogen bonding characteristics of hydroxyl groups in glucose aqueous solutions with different concentrations. The hydrogen bonding abilities and strength of different O and H atom types have been calculated and compared. The acceptor/donor efficiencies have been predicted and it has been found that: (1) O2-HO2 and O3-HO3 are more efficient intramolecular hydrogen bonding acceptors than donors; (2) O1-HO1, O4-HO4 and O6-HO6 are more efficient intramolecular hydrogen bonding donors than acceptors; (5) O1-HO1 and O6-HO6 are more efficient intermolecular hydrogen bonding acceptors than donors while hydroxyl groups O2-HO2 and O4-HO4 are more efficient intermolecular hydrogen bonding donors than acceptors. The hydrogen bonding abilities of hydroxyl groups revealed that: (1) the hydrogen bonding ability of OH2-$H_w$ is larger than that of hydroxyl groups in glucose; (2) among the hydroxyl groups in glucose, the hydrogen bonding ability of O6-HO6 is the largest and the hydrogen bonding ability of O4-HO4 is the smallest; (3) the intermolecular hydrogen bonding ability of O6-HO6 is the largest; (4) the order for intramolecular hydrogen bonding abilities (from large to small) is O2-HO2, O1-HO1, O3-HO3, O6-HO6 and O4-HO4.

Infrared Spectroscopic Study of Molecular Hydrogen Bonding in Chiral Smetic Liquid Crystal

  • Jang, Won-Gun
    • Journal of Information Display
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    • v.2 no.3
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    • pp.18-31
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    • 2001
  • We utilize Fourier transform infrared (IR) spectroscopy to probe intramolecular hydrogen bonding in $smectic-C^{\ast}$ liquid crystal phases. Infrared spectra of aligned smectic liquid crystal materials vs. temperature and of isotropic liquid crystal mixtures vs. concentration were measured in homologs, both with and without hydrogen bonding. Hydrogen bonding significantly changes the direction and magnitude of the vibrational dipole transition moments, causing marked changes in the IR dichroic absorbance profiles of hydrogen bonded molecular subfragments. A GAUSSIAN94 computation of the directions, magnitudes, and frequencies of the vibrational dipole moments of molecular subfragments shows good agreement with the experimental data. The results show that IR dichroism can be an effective probe of hydrogen bonding in liquid crystal phases.

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Effect of Draw Ratio on the Surface Energy of Polycapramide Film (연신비가 폴리카프라미드 막의 표면 에너지에 미치는 영향)

  • 하완식;류동일;김정수
    • Textile Science and Engineering
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    • v.17 no.1
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    • pp.26-30
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    • 1980
  • Critical surface tension γc, dispersion γsd, polar γsp including hydrogen bonding, polar γspr excluding hydrogen bonding, and hydrogen bonding γsh contributions of the solid surface tension γs for polycapramide film prepared under various draw ratios were determined by Zisman's plot, Kaelble's computational analysis and extended Fowkes' equation, respectively. It is indicated that the increase in γs of the film surface with draw ratio is mainly due to hydrogen bonding contribution.

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The Bonding of Interstitial Hydrogen in the NiTi Intermetallic Compound

  • Kang, Dae-Bok
    • Bulletin of the Korean Chemical Society
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    • v.27 no.12
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    • pp.2045-2050
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    • 2006
  • The interstitial hydrogen bonding in NiTi solid and its effect on the metal-to-metal bond is investigated by means of the EH tight-binding method. Electronic structures of octahedral clusters $Ti_4Ni_2$ with and without hydrogen in their centers are also calculated using the cluster model. The metal d states that interact with H 1s are mainly metal-metal bonding. The metal-metal bond strength is diminished as the new metal-hydrogen bond is formed. The causes of this bond weakening are analyzed in detail.

Excited State Dynamics of Curcumin and Solvent Hydrogen Bonding

  • Yang, Il-Seung;Jin, Seung-Min;Kang, Jun-Hee;Ramanathan, Venkatnarayan;Kim, Hyung-Min;Suh, Yung-Doug;Kim, Seong-Keun
    • Bulletin of the Korean Chemical Society
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    • v.32 no.spc8
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    • pp.3090-3093
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    • 2011
  • Curcumin is a natural product with antioxidant, anti-inflammatory, antiviral and antifungal functions. As it is known that the excited state intramolecular hydrogen transfer of curcumin are related to its medicinal antioxidant mechanism, we investigated its excited state dynamics by using femtosecond transient absorption spectroscopy in an effort to understand the molecule's therapeutic effect in terms of its photophysics and photochemistry. We found that stronger intermolecular hydrogen bonding with solvents weakens the intramolecular hydrogen bonding and decelerates the dynamical process of the enolic hydrogen. Exceptions are found in methanol and ethylene glycol due to their nature as simultaneous hydrogen bonding donor-acceptor and high viscosity solvent, respectively.

Molecular Dynamics Investigation of the Effects of Concentration on Hydrogen Bonding in Aqueous Solutions of Methanol, Ethylene Glycol and Glycerol

  • Zhang, Ning;Li, Weizhong;Chen, Cong;Zuo, Jianguo;Weng, Lindong
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2711-2719
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    • 2013
  • Hydrogen bonding interaction between alcohols and water molecules is an important characteristic in the aqueous solutions of alcohols. In this paper, a series of molecular dynamics simulations have been performed to investigate the aqueous solutions of low molecular weight alcohols (methanol, ethylene glycol and glycerol) at the concentrations covering a broad range from 1 to 90 mol %. The work focuses on studying the effect of the alcohols molecules on the hydrogen bonding of water molecules in binary mixtures. By analyzing the hydrogen bonding ability of the hydroxyl (-OH) groups for the three alcohols, it is found that the hydroxyl group of methanol prefers to form more hydrogen bonds than that of ethylene glycol and glycerol due to the intra-and intermolecular effects. It is also shown that concentration has significant effect on the ability of alcohol molecule to hydrogen bond water molecules. Understanding the hydrogen bonding characteristics of the aqueous solutions is helpful to reveal the cryoprotective mechanisms of methanol, ethylene glycol and glycerol in aqueous solutions.

Computational Study of Hydrogen Bonding in Phenol-acetonitrile-water Clusters

  • Ahn, Doo-Sik;Lee, Sung-Yul;Cheong, Won-Jo
    • Bulletin of the Korean Chemical Society
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    • v.25 no.8
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    • pp.1161-1164
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    • 2004
  • Calculations are presented for phenol ?acetonitrile - $(water)_n$ (n = 1-3) clusters. We examine the nature of interactions in the mixed clusters by calculating and comparing the structures, relative energies and harmonic frequencies of isomers with different type of hydrogen bonding. The conformers exhibit quite different patterns in the shifts of the CN and OH stretching frequencies, depending on the type of hydrogen bonding. Cyclic hydrogen bonding among the water molecule(s), acetonitrile and phenolic OH proves very important in determining the relative stability. It is also shown that acetonitrile tends to bind to the OH group of phenol in low energy conformers.

Hydrogen Bonds in GlcNAc( β1,3)Gal( β)OMe in DMSO Studied by NMR Spectroscopy and Molecular Dynamics Simulations

  • Shim, Gyu-Chang;Shin, Jae-Min;Kim, Yang-Mee
    • Bulletin of the Korean Chemical Society
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    • v.25 no.2
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    • pp.198-202
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    • 2004
  • Hydrogen bond is an important factor in the structures of carbohydrates. Because of great strength, short range, and strong angular dependence, hydrogen bonding is an important factor stabilizing the structure of carbohydrate. In this study, conformational properties and the hydrogen bonds in GlcNAc( ${\beta}$1,3)Gal(${\beta}$)OMe in DMSO are investigated through NMR spectroscopy and molecular dynamics simulation. Lowest energy structure in the adiabatic energy map was utilized as an initial structure for the molecular dynamics simulations in DMSO. NOEs, temperature coefficients, SIMPLE NMR data, and molecular dynamics simulations proved that there is a strong intramolecular hydrogen bond between O7' and HO3' in GlcNAc( ${\beta}$1,3)Gal(${\beta}$)OMe in DMSO. In aqueous solution, water molecule makes intermolecular hydrogen bonds with the disaccharides and there was no intramolecular hydrogen bonds in water. Since DMSO molecule is too big to be inserted deep into GlcNAc(${\beta}$1,3)Gal(${\beta}$)OMe, DMSO can not make strong intermolecular hydrogen bonding with carbohydrate and increases the ability of O7' in GlcNAc(${\beta}$1,3)Gal(${\beta}$)OMe to participate in intramolecular hydrogen bonding. Molecular dynamics simulation in conjunction with NMR experiments proves to be efficient way to investigate the intramolecular hydrogen bonding existed in carbohydrate.

The Near Infrared Spectroscopic Studies of the Hydrogen Bonding Between Thioacetamide and Azines in Nonaqueous Solutions

  • 이상현;박정희;윤창주;최영상
    • Bulletin of the Korean Chemical Society
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    • v.16 no.9
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    • pp.831-834
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    • 1995
  • The nature of hydrogen bonding between thioacetamide and azines has been thoroughly investigated using near IR absorption spectroscopy. The νN-H + amide II combination band in thioacetamide (TA) has been analyzed to determine the thermodynamic constants for the formation of hydrogen bonded 1:1 TA:azine complexes in CCl4 and CHCl3 solutions. The relative stabilities of TA-azine complexes (pyridine->1,2-diazine->1,3-diazine->1,4-diazine-TA) are in good agreement with the relative proton affinities of azines in the gas phase. The results serve as a basis for analyzing the factors which influence the hydrogen bonding formation of TA in nonaqueous solutions.

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Solvatochromic Effects and Hydrogen Bonding Interactions of 4-(4-Nitrophenylazo)-1-naphthol Derivatives

  • 신동명;권오악
    • Bulletin of the Korean Chemical Society
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    • v.16 no.7
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    • pp.574-577
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    • 1995
  • Solvatochromic effect and hydrogen bonding interaction of NPNOH, NPNO- and NPNOR were investigated. Electronic transition energies of the dyes were plotted against empirical solvent polarity parameters, Taft's π* and Reichardt's ET(30). Good correlations were observed when the excitation energies were plotted against the energy calculated by multiple linear regression method which was developed by Taft. There is an intrinsic difference between betaine for ET(30) polarity scale and the azoderivative, which is derived from the specific hydrogen bond incurred with probe molecules and solvents. The hydrogen bonding plays a very important role for stabilization of an excited state molecule by solvents especially when a solute possesses a negative charge as with NPNO-.

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