摘要
采用密度泛函理论B3LYP方法,在6-311++G(d,p)基组水平研究了HO2与CH2S的微观反应机理.在CCSD(T)/6-311++G(d,p)//B3LYP/6-311++G(d,p)水平上获得了势能面.利用经典过渡态理论(TST)与变分过渡态理论(CVT)并结合小曲率隧道效应模型(SCT),计算了反应通道在200～2500 K温度范围内的速率常数kTST,kCVT和kCVT/SCT.找到了该反应体系的6个反应通道,其中HO2的端位O进攻CH2S中C生成的HOOCH2S及其异构化得到的OOCH2SH均为主反应产物.动力学数据也表明,当温度低于1400 K时,通道(1a)HO2+CH2S→TS1/P1→HOOCH2S是主反应通道,高于1400 K时,通道(2a)HO2+CH2S→TS2/P1→HOOCH2S占优势.
The reaction mechanism of HO2 with CH2S was investigated at the B3LYP/6-311＋＋G（d,p） level.Energetic information of stationary points and the points along the minimum energy path is further re-fined at the CCSD（T）/6-311＋＋G（d,p） level.The rate constants of these channels in the temperature range of 200～2500 K were evaluated by means of the classical transition state theory（TST） and the canonical variational transition state theory（CVT） conjunction with the small-curvature tunneling correction（SCT）.Six possible reaction channels have been identified for the title reaction.Based on the potential energy sur-face and the kinetics,it can be concluded that HOOCH2S,formed via the end O atom of the HO2 radical at-tacking on the C atom of the CH2S molecule,and its isomer OOCH2SH are the major products.When the temperature is lower than 1400 K,the channel（1a） HO2＋CH2S→TS1/P1→HOOCH2S is the major reaction path,while the channel（2a） HO2＋CH2S→TS2/P1→HOOCH2S becomes the favorable reaction path when the temperature is higher than 1400 K.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2011年第17期1957-1964,共8页
Acta Chimica Sinica
基金
国家自然科学基金(Nos.20973053
20801017
21073051)
河北省自然科学基金(Nos.B2010000371
B2011205058)
河北省高等学校科学研究项目(No.Z2010166)
石家庄学院自然科学研究基金项目(No.10ZDA001)资助项目
