CH_3S与O_2气相反应机理的理论研究

Theoretical Study of the Gas Phase Reaction of CH_3S with O_2

在G3(MP2 )水平上 ,通过对CH3 S与O2 反应势能面 (PES)上关键驻点的能量计算 ,共找到 4种中间体 ,9个过渡态 ,6种产物通道 ,并对这些气相反应机理进行了讨论 ,同时应用TST RRKM理论对主要反应的速率进行计算 .结果表明 :CH3 S与O2 反应在低温下以生成CH3 SOO为主 ,并与实验结果吻合 ;在中高温下以加成消去和抽提反应为主 ,分别生成CH3 +SO2 和CH2 S +HO2 ,其它产物较少 .

A series of key stationary points of potential energy surface (PES) for the CH3S + O-2 system was calculated at the G3 (MP2) level. The calculations reveal four intermediates, nine transition states and six product channels. With the stationary points and TST-RRKM theory, the reaction rates are calculated, gas phase reaction mechanism of CH3S + O-2 is discussed. At low temperature, the reaction producing CH3SOO is the main channel. At high temperature, the addition elimination mechanism giving products of CH3 + SO2 and H-abstraction mechanism giving products of CH2S + HO2 are dominant reaction channels, the other products might be neglected.