Hydrogen bonding density functional theory studies

Density functional theory study of aqueous-phase rate acceleration and endo/exo selectivity of the butadiene and acrolein Diels-Alder reaction72 shows that approximately 50% of the rate acceleration and endo/exo selectivity is attributed to hydrogen bonding and the remainder to bulk-phase effects, including enforced hydrophobic interactions and cosolvent effects. This appears to be supported by the experimental results of Engberts where a pseudothermodynamic analysis of the rate acceleration in water relative to 1-propanol and 1-propanol-water mixtures indicates that hydrogen-bond stabilization of the polarized activated complex and the decrease of the hydrophobic surface area of the reactants during the activation process are the two main causes of the rate enhancement in water.13... 

A.J. Bienko et al., Low barrier hydrogen bond in protonated proton sponge. X-ray diffraction, infrared, and theoretical ab initio density functional theory studies. J. Chem. Phys. 119, 4313 4319 (2003)... 

Ireta J, Neugebauer J, Scheffler M, Rojo A, Galvan M (2003) Density functional theory study of the cooperativity of hydrogen bonds in finite and infinite o helices. J Phys Chem B 107 1432—1437... 

Wieczorek R, Dannenberg JJ (2003b) Hydrogen bond cooperativity, vibrational coupling, and dependence of helix stability on changes in amino acid sequence in small 3io-helical peptides. A density functional theory study. J Am Chem Soc 125 14065-14071... 

Density functional theory study of the hydrogen-bonded pyridine-H20 complex A comparison with RHF and MP2 methods and with experimental data ... 

P. Salvador, J.J. Dannenberg, Dependence upon basis sets of trans hydrogen-bond 13C-15N 3-bond and other scalar J-couphngs in amide dimers used as peptide models. A density functional theory study,. Phys. Chem. B 108 (2004) 15370. 

Katsyuba, S.A., Vener, M.V, Zvereva, E.E., Fei, Z., Scopelliti, R., Laurenczy, G., Yan, N., Paunescu, E. and Dyson, P. J., How strong is hydrogen bonding in ionic liquids Combined X-ray crystallographic, infrared/Raman spectroscopic, and density functional theory study, J. Phys. Chem. B 117, 9094-9105 (2013). 

Detection of the dA N1 and dC N3 adducts may not in one sense be particularly important for DNA based on their central position within the helical conformation and hydrogen bonding network.37,38 Still, the deoxynucleoside studies helped to focus attention on the reversibility of alkylation by QM and provided insight into the reactions of duplex DNA described below in Section 9.3. Reaction at the deoxynucleoside level also provided an essential system for developing a theoretical treatment of QM reaction.50-52 Computations based on density functional theory well rationalized the published results on d A and correctly anticipated the results on dG and dC reviewed above and described in more detail in Chapter 2 (Freccero). 

Adsorption of cyanide anions can be affected by adsorption of cations. In the solutions containing nonspecifically adsorbed anions, the nature of alkali metal cations was found to influence the measured value of the electrode capacitance at potentials more negative than —0.6 V (versus standard hydrogen electrode (SHE)). At < —l.OV adsorption of CN ions was enhanced in the presence of Li+ and Na+ cations, and inhibited in the presence of Cs+ ions [81]. A combined SERS and density-functional theory has been applied to study cyanide adsorption at Au electrode [82]. The authors have arrived at the conclusion that the polarity of Au—CN bonds falls between that of Au—Cl and Au—Br surface bonds. The binding strength for three different gold surfaces decreased in the order ... 

The hydrogen bonding model for rationalizing regioselectivities was further studied by Manuel Martin-Lomas and coworkers. Density functional theory (DFT) calculations... 

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