Imaging nucleophilic substitution dynamics

被引：312

作者：

Mikosch, J. ^{[1
]}

Trippel, S. ^{[1
]}

Eichhorn, C. ^{[1
]}

Otto, R. ^{[1
]}

Lourderaj, U. ^{[2
]}

Zhang, J. X. ^{[2
]}

Hase, W. L. ^{[2
]}

Weidemueller, M. ^{[1
]}

Wester, R. ^{[1
]}

机构：

[1] Univ Freiburg, Inst Phys, D-79104 Freiburg, Germany

[2] Texas Tech Univ, Dept Chem & Biochem, Lubbock, TX 79409 USA

来源：

SCIENCE | 2008年 / 319卷 / 5860期

关键词：

D O I：

10.1126/science.1150238

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Anion- molecule nucleophilic substitution ( SN2) reactions are known for their rich reaction dynamics, caused by a complex potential energy surface with a submerged barrier and by weak coupling of the relevant rotational- vibrational quantum states. The dynamics of the SN2 reaction of Cl- + CH3I were uncovered in detail by using crossed molecular beam imaging. As a function of the collision energy, the transition from a complex- mediated reaction mechanism to direct backward scattering of the I- product was observed experimentally. Chemical dynamics calculations were performed that explain the observed energy transfer and reveal an indirect roundabout reaction mechanism involving CH3 rotation.

引用

页码：183 / 186

页数：4

共 29 条

[1] Gas-phase SN2 and bromine abstraction reactions of chloride ion with bromomethane:: Reaction cross sections and energy disposal into products [J].