کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5418959 | 1506986 | 2006 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Central barrier recrossing dynamics of the Clâ+CD3Cl SN2 reaction
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A direct dynamics simulation, at the MP2/6-31G* level of theory, was performed for the Clâ+CD3Cl SN2 reaction. An ensemble of 88 trajectories was initiated at the [Cl-Â -CD3-Â -Cl]â central barrier, in accord with a 300Â K Boltzmann distribution, and integrated in both the forward and reverse directions off the barrier. The dynamics of these trajectories are inconsistent with both RRKM theory and transition state theory (TST). Only 1% of the trajectories dissociate to Clâ+CD3Cl products in comparison to the RRKM prediction of greater than 50%. Also, in contrast to the assumption of TST and prediction of RRKM theory, recrossings of the central barrier are observed in the trajectories, giving rise to an upper limit of 0.7 for the correction factor to the 300Â KÂ TST rate constant. The results of this study are compared with a previous direct dynamics simulation, also at the MP2/6-31G* level of theory, of the central barrier dynamics for the Clâ+CH3Cl SN2 reaction. Both reactions exhibit extensive non-RRKM dynamics. However, central barrier recrossings are more important for the Clâ+CH3Cl reaction and the upper limit to its TST correction factor is 0.2.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure: THEOCHEM - Volume 771, Issues 1â3, 12 October 2006, Pages 27-31
Journal: Journal of Molecular Structure: THEOCHEM - Volume 771, Issues 1â3, 12 October 2006, Pages 27-31
نویسندگان
Sueun Cheon, Kihyung Song, William L. Hase,