Theoretical Study of SO2 Formation in the Reaction of CH3S Radical with NO2，O3，O2 and HO2 in the Gas Phase

• Main Authors: Yu Bin Ting, 余璧婷
• Other Authors: Ho Jia Jen
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/22119672535401874226

碩士 === 國立臺灣師範大學 === 化學系 === 93 === This thesis deals with the calculation of tropospheric reaction of methylthiyl radical(CH3S) with NO2，O3，O2 and HO2 to check the formation of SO2 by ab initio theory at MP2/6-311G(d) level. There are four major sections to describe the reaction mechanisms. Section 1: We study the reaction between methylthiyl radical and nitrogen dioxide(NO2) in the gas phase . The reaction proceeds with the participation of NO2 by twice or three times to produced sulfur dioxide. The formation energy is relatively large and the product is stable. Therefore, we think the reaction of methylthiyl radical with nitrogen dioxide to produce sulfur dioxide is very possible. Section 2: We studied the reaction of CH3S with O3.We found out that with the participation of O3 two times it is possible to form CH3SO2 and than dissociated to SO2.We detect the reaction of methylthiyl radical with ozone twice to produce CH3SO2.After that, we through the thermal decomposition of CH3SO2 and we can get SO2. Section 3: We studied the reaction of CH3S+O2. We found out that the cleavage energy of O-O bond of intermediate is quite high. As a consequence, it is not possible for the formation of SO2 via this process. Section 4: We studied the reaction of CH3S+HO2.We found out that the intermediates D2 and D5 are very stable, and it seems not possible to proceed further to produce SO2 in this reaction.