کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9591027 1507005 2005 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
DFT explorations of tautomerism of 2-mercaptoimidazole in aqueous solution
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
DFT explorations of tautomerism of 2-mercaptoimidazole in aqueous solution
چکیده انگلیسی
A systematic investigation of the proton transfer in the tautomerization of 2-mercaptoimidazole was undertaken. Calculations in aqueous solution were performed using the combined supramolecular/continuum and the direct continuum models, respectively. Complexes containing one and two water molecules around the hydrophilic site of 2-mercaptoimidazole were used for the combined supramolecular/continuum calculation. DFT results predict that the barrier height for non-water-assisted intramolecular proton transfer is very high (175.8 kJ/mol). Hydrogen bonding between 2-mercaptoimidazole and the water molecule(s) will dramatically lower the barrier by the concerted multiple proton transfer mechanism. The proton transfer process through a eight-member ring formed by 2-mercaptoimidazole and two water molecules is found to be more efficient one and the calculated barrier height is reduced to ca. 72 kJ/mol.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure: THEOCHEM - Volume 730, Issues 1–3, 7 October 2005, Pages 199-205
نویسندگان
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