中文摘要：

在G3XMP2／／B3LYP／6-311＋G（3df,2p）水平上对CH3SO3裂解反应的机理进行了研究，获得了6条通道（10条路径），并构建了其势能剖面．同时采用单分子反应理论计算了各个通道在温度200—3000K区间的速率常数．研究结果表明，在计算温度范围内，CH3SO3裂解反应的主产物为P1（CH3＋SO3），产物P2（CH3O＋SO3）和P3（HCHO＋HOSo）仅在温度大于3000K时对总产物有贡献，而产物P4（CHSO2＋H2O）、P5（CH2SO3＋H）和P6（CHSO3＋H2）贡献相对较少．将裂解反应总的速率常数拟合为ktotal=1．40x1012To015exp（-7831．58／T．此外，根据统计热力学原理，预测了所有物种的生成焓（△fh298，△fHok）、熵（S289K）和热容（Gp1298—2000K），计算的结果与实验值较接近．

英文摘要：

The mechanism and kinetics of unimolecular decomposition of CH3SO3 are studied at the G3XMP2//B3LYP/6-311 ＋G（3df,2p） level of theory. Six possible dissociation channels and potential energy surface for the CH3SO3 decomposition are investigated. Rate constants over the temperature range of 200-3000 K are calculated using Rice-Ramsperger-KasseI-Marcus （RRKM） theory. The results indicate that the product PI（CH3＋SO3） is dominant between 200-3000 K. Products P2（CH30＋SO2） and P3（HCHO＋ HOSO） increase significantly at higher temperatures （〉3000 K）. Products P4（CHSO2＋H2O）, P5（CH2SO3＋H）, and P6（CHSO3＋ H2） show little formation in the temperature range （200-3000 K）. The total rate constant can be expressed as ktotal=1.40 x 1012T0.15exp（-7831.58/T）. Thermodynamic properties including enthalpies of formation （A,H~BK, A,H0k）, entropies e （$298K）, and heat capacities （Cp1 298-2000 K） of all the minima and transition states are predicted from statistical mechanics, and found to be in good agreement with the available experimental values.