𝔖 Bobbio Scriptorium
✦   LIBER   ✦

DFT and Ab initio direct dynamics studies on the hydrogen abstraction reactions of chlorine atoms with CH4−nFn (n = 1–3)

✍ Scribed by Jing-Fa Xiao; Ze-Sheng Li; Jing-Yao Liu; Li Sheng; Chia-Chung Sun

Publisher
John Wiley and Sons
Year
2002
Tongue
English
Weight
168 KB
Volume
23
Category
Article
ISSN
0192-8651

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

A direct dynamics study is carried out for the hydrogen abstraction reactions Cl + CH~4−n~F~n~ (n = 1–3) in the temperature range of 200–1000 K. The minimum energy paths (MEPs) of these reactions are calculated at the BH&H‐LYP/6‐311G(d,p) level, and the energies along the MEPs are further refined at the QCISD(T)/6‐311+G(2df,2p) and QCISD(T)/6‐311+G(d,p) (single‐point) level. The rate constants obtained by using the improved canonical variational transition state theory incorporating small‐curvature tunneling correction (ICVT/SCT) are in good agreement with the available experimental results. It is shown that the vibrational adiabatic potential energy curves for these reactions have two barriers, a situation similar to the analogous reactions CH~3~X+Cl (X=Cl, Br). The theoretical results show that for the title reactions the variational effect should not be neglected over the whole considered temperature range, while the small‐curvature tunneling effect is only important in the lower temperature range. The effects of fluorine substitution on the rate of this kind of reactions are also examined. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 1456–1465, 2002

📜 SIMILAR VOLUMES

Ab initio direct dynamics studies on the
Ab initio direct dynamics studies on the reaction of H atom with CH3CH2Cl
✍ Li Sheng; Ze-Sheng Li; Jing-Yao Liu; Jing-Fa Xiao; Chia-Chung Sun 📂 Article 📅 2003 🏛 John Wiley and Sons 🌐 English ⚖ 240 KB 👁 1 views

The multiple channel reaction H + CH(3)CH(2)Cl --> products has been studied by the ab initio direct dynamics method. The potential energy surface information is calculated at the MP2/6-311G(d,p) level of theory. The energies along the minimum energy path are further improved by single-point energy

Direct ab initio dynamics studies on the
Direct ab initio dynamics studies on the hydrogen-abstraction reactions of OH radicals with HOX (X = F, Cl, and Br)
✍ Li Wang; Jing-Yao Liu; Ze-Sheng Li; Chia-Chung Sun 📂 Article 📅 2004 🏛 John Wiley and Sons 🌐 English ⚖ 153 KB 👁 2 views

The hydrogen abstract reactions of OH radicals with HOF (R1), HOCl (R2), and HOBr (R3) have been studied systematically by a dual-level direct-dynamics method. The geometries and frequencies of all the stationary points are optimized at the MP2/6-311+G(2d, 2p) level of theory. A hydrogen-bonded comp

Direct ab initio dynamics study on the r
Direct ab initio dynamics study on the rate constants and kinetic isotope effect for the reactions of H atoms with GeDn(CH3)4−n (n = 1–4)
✍ Yang Wu; Yi-Hong Ding; Jing-Fa Xiao; Ze-Sheng Li; Xu-Ri Huang; Chia-Chung Sun 📂 Article 📅 2002 🏛 John Wiley and Sons 🌐 English ⚖ 177 KB 👁 1 views

Direct ab initio dynamic calculations are performed on the reactions of atomic hydrogen with GeD(n)(CH(3))(4-n) (n = 1-4) over the temperature range 200-2000 K at the PMP4SDTQ/6-311 +G(3df,2p)//MP2/6-31 +G(d) (for n = 2-4) and G2//MP2/6-31 +G(d) (for n = 1) levels. The corresponding k(H)/k(D) ratios

Direct Ab Initio Dynamics Study on the R
Direct Ab Initio Dynamics Study on the Reaction of CH3CHF2 (HFC-152a) with the Cl Atom
✍ Hao Sun; Hongqing He; Jingyao Liu; Zesheng Li; Xiumei Pan; Rongshun Wang 📂 Article 📅 2008 🏛 John Wiley and Sons 🌐 English ⚖ 226 KB 👁 1 views

## Abstract A direct ab initio dynamics method is used to investigate the hydrogen‐abstraction reaction CH~3~CHF~2~+Cl. One transition state is located for α‐H abstraction, and two are identified for β‐H abstraction. The potential‐energy surface (PES) is obtained at the G3(MP2)//MP2/6‐311G(d, p) le

Kinetic mechanism of the hydrogen abstra
Kinetic mechanism of the hydrogen abstraction reactions of the chlorine atoms with CH3CF2Cl and CH3CFCl2: A dual level direct dynamics study
✍ Yue-meng Ji; Xiao-lei Zhao; Ze-sheng Li; Jing-yao Liu 📂 Article 📅 2007 🏛 John Wiley and Sons 🌐 English ⚖ 396 KB 👁 1 views

## Abstract The mechanisms of the reactions: CH~3~CFCl~2~ + Cl (R1) and CH~3~CF~2~Cl + Cl (R2) are studied over a wide temperature range (200–3000 K) using the dual‐level direct dynamics method. The minimum energy path calculation is carried out at the MP2/6‐311G(d,p) and B3LYP/6‐311G(d,p) levels,