计算机与应用化学
計算機與應用化學
계산궤여응용화학
COMPUTERS AND APPLIED CHEMISTRY
2013年
11期
1310-1314
,共5页
石从云%胡威%娄菲%范淑珍
石從雲%鬍威%婁菲%範淑珍
석종운%호위%루비%범숙진
理论计算%反应机理%氯代次甲基(CCl)%臭氧(O3)
理論計算%反應機理%氯代次甲基(CCl)%臭氧(O3)
이론계산%반응궤리%록대차갑기(CCl)%취양(O3)
theoretical calculation%reaction mechanism%chlorinated methylidyne radical (CCl)%ozone (O3)
臭氧层损耗是人类面临的重要环境问题之一。平流层中氟氯烃类化合物受紫外线光解所产生的氯代次甲基会消耗臭氧。为了弄清该自由基消耗臭氧的机制，用量子化学计算的方法详细地研究了CCl+O3反应在二重态势能面上的反应机理。本文在B3LYP/6-311G(d, p)水平上优化了反应物、中间体、过渡态和产物的几何构型，得到了相应的振动频率和能量值，并在相同水平上用内禀反应坐标计算方法确认了过渡态和中间体之间的联系，理清了该反应详细的路径。研究发现CCl+O3反应有5种产物通道：ClCO+O2、CO2+Cl+O、CO2+ClO、CO+O2+Cl和OCO2+Cl，通过对各反应路径上的驻点的能量分析得出ClCO+O2是主要的通道，CO2+Cl+O、CO2+ClO和OCO2+Cl是次要通道，通道CO+O2+Cl在动力学上是最少的。本研究工作将为控制氯代次甲基对臭氧层的破坏提供理论依据。
臭氧層損耗是人類麵臨的重要環境問題之一。平流層中氟氯烴類化閤物受紫外線光解所產生的氯代次甲基會消耗臭氧。為瞭弄清該自由基消耗臭氧的機製，用量子化學計算的方法詳細地研究瞭CCl+O3反應在二重態勢能麵上的反應機理。本文在B3LYP/6-311G(d, p)水平上優化瞭反應物、中間體、過渡態和產物的幾何構型，得到瞭相應的振動頻率和能量值，併在相同水平上用內稟反應坐標計算方法確認瞭過渡態和中間體之間的聯繫，理清瞭該反應詳細的路徑。研究髮現CCl+O3反應有5種產物通道：ClCO+O2、CO2+Cl+O、CO2+ClO、CO+O2+Cl和OCO2+Cl，通過對各反應路徑上的駐點的能量分析得齣ClCO+O2是主要的通道，CO2+Cl+O、CO2+ClO和OCO2+Cl是次要通道，通道CO+O2+Cl在動力學上是最少的。本研究工作將為控製氯代次甲基對臭氧層的破壞提供理論依據。
취양층손모시인류면림적중요배경문제지일。평류층중불록경류화합물수자외선광해소산생적록대차갑기회소모취양。위료롱청해자유기소모취양적궤제，용양자화학계산적방법상세지연구료CCl+O3반응재이중태세능면상적반응궤리。본문재B3LYP/6-311G(d, p)수평상우화료반응물、중간체、과도태화산물적궤하구형，득도료상응적진동빈솔화능량치，병재상동수평상용내품반응좌표계산방법학인료과도태화중간체지간적련계，리청료해반응상세적로경。연구발현CCl+O3반응유5충산물통도：ClCO+O2、CO2+Cl+O、CO2+ClO、CO+O2+Cl화OCO2+Cl，통과대각반응로경상적주점적능량분석득출ClCO+O2시주요적통도，CO2+Cl+O、CO2+ClO화OCO2+Cl시차요통도，통도CO+O2+Cl재동역학상시최소적。본연구공작장위공제록대차갑기대취양층적파배제공이론의거。
The depletion of the ozone layer is one of the important environmental problems. The chlorinated methylidyne radical produced by UV photolysis of CFC in the stratosphere will consume the ozone. In order to clarify the ozone depletion mechanism by the radical, we employed quantum chemical calculations to study the reaction mechanisms of CCl radical with O3 on the doublet potential energy surface. The geometric structures of reactants, intermediates, transition states and products were optimized at the B3LYP/6-311G(d, p) level, and their vibration frequencies and energy values were obtained. Intrinsic reaction coordinate calculations at the same level were implemented to confirm the connections between transition states and intermediates. The detailed reaction pathways were made clear. It is found that the CCl + O3 reaction possesses five product channels:ClCO+O2, CO2+Cl+O, CO2+ClO, CO+O2+Cl, OCO2+Cl. Through the energy analysis of the stationary points on each reaction pathway, we can drawn the conclusion that the ClCO+O2 channel is the most feasible, CO2+Cl+O, CO2+ClO and OCO2+Cl are all secondary channels, the CO+O2+Cl channel is the least competitive. This research will provide theoretical basis for controlling the destruction of the ozone layer by the chlorinated methylidyne radical.
