KULHÁNEK, Petr, Edward W. SCHLAG a Jaroslav KOČA. Mechanism of Proton Transfer in Short Protonated Oligopeptides. 1. N-Methylacetamide and N2-Acetyl-N1-methylglycinamide. J. Phys. Chem. A. American Chemical Society, 2003, roč. 107, č. 30, s. 5789-5797, 8 s. ISSN 1089-5639. |
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@article{489312, author = {Kulhánek, Petr and Schlag, Edward W. and Koča, Jaroslav}, article_number = {30}, keywords = {proton transfer; proton exchange; proton interaction; DFT}, language = {eng}, issn = {1089-5639}, journal = {J. Phys. Chem. A}, title = {Mechanism of Proton Transfer in Short Protonated Oligopeptides. 1. N-Methylacetamide and N2-Acetyl-N1-methylglycinamide}, url = {http://dx.doi.org/10.1021/jp027689+}, volume = {107}, year = {2003} }
TY - JOUR ID - 489312 AU - Kulhánek, Petr - Schlag, Edward W. - Koča, Jaroslav PY - 2003 TI - Mechanism of Proton Transfer in Short Protonated Oligopeptides. 1. N-Methylacetamide and N2-Acetyl-N1-methylglycinamide JF - J. Phys. Chem. A VL - 107 IS - 30 SP - 5789-5797 EP - 5789-5797 PB - American Chemical Society SN - 10895639 KW - proton transfer KW - proton exchange KW - proton interaction KW - DFT UR - http://dx.doi.org/10.1021/jp027689+ N2 - A study of proton transfer in models of a single peptide unit (N-methylacetamide) and diamide (N2-acetyl-N1-methylglycinamide) as well as the influence of a single water molecule on proton transfer is presented here. Three proton pathways in protonated N-methylacetamide are considered: isomerization, inversion, and 1,3-proton shift. The isomerization step exhibits the lowest energy barrier. When a single water molecule was added, no significant influence on proton isomerization was observed. In the diamide model, the isomerization-jump mechanism of proton transfer along diamide carbonyl oxygens was inspected, and the proton isomerization steps were found to be the most energy-demanding processes (~17 kcal mol-1). The presence of a single water molecule leads to a different, lower-energy-barrier proton-transfer mechanism with proton exchange. The highest energy barrier is only 7.6 kcal mol-1. Possible competing pathways are also discussed. ER -
KULHÁNEK, Petr, Edward W. SCHLAG a Jaroslav KOČA. Mechanism of Proton Transfer in Short Protonated Oligopeptides. 1. N-Methylacetamide and N2-Acetyl-N1-methylglycinamide. \textit{J. Phys. Chem. A}. American Chemical Society, 2003, roč.~107, č.~30, s.~5789-5797, 8 s. ISSN~1089-5639.
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