物理化学学报
物理化學學報
물이화학학보
ACTA PHYSICO-CHIMICA SINICA
2011年
4期
801-807
,共7页
宋磊%于锋%吴琍霞%周晓国%刘世林
宋磊%于鋒%吳琍霞%週曉國%劉世林
송뢰%우봉%오리하%주효국%류세림
羟基负离子%氟氯代甲烷%反应机理%质子转移%亲核取代(SN2)反应
羥基負離子%氟氯代甲烷%反應機理%質子轉移%親覈取代(SN2)反應
간기부리자%불록대갑완%반응궤리%질자전이%친핵취대(SN2)반응
Hydroxide anion%Chlorofluoromethane%Reaction mechanism%Proton transfer%Nucleophilic substitution (SN2) reaction
理论研究了羟基负离子(OH-)与氟氯代甲烷(CH2CIF)反应的阴离子产物通道.分别在B3LYP/6-31+G(d,p)和B3LYP/6-311++G(2d,p)水平上得到反应势能面上各关键物种的优化构型,进而计算得到谐振频率和零点能.基于CCSD(T)/6-311+G(3df,3dp)水平的相对能量,描述了由质子转移和双分子亲核取代(SN2)过程生成各阴离子产物的途径.各阴离子产物途径势垒的计算结果表明质子转移过程是实验中的主要产物通道,与以往实验测量的结论相符.此外,计算还显示双分子亲核取代过程得到了非典型的阴离子产物,其中动力学效应可能会导致F-的生成.
理論研究瞭羥基負離子(OH-)與氟氯代甲烷(CH2CIF)反應的陰離子產物通道.分彆在B3LYP/6-31+G(d,p)和B3LYP/6-311++G(2d,p)水平上得到反應勢能麵上各關鍵物種的優化構型,進而計算得到諧振頻率和零點能.基于CCSD(T)/6-311+G(3df,3dp)水平的相對能量,描述瞭由質子轉移和雙分子親覈取代(SN2)過程生成各陰離子產物的途徑.各陰離子產物途徑勢壘的計算結果錶明質子轉移過程是實驗中的主要產物通道,與以往實驗測量的結論相符.此外,計算還顯示雙分子親覈取代過程得到瞭非典型的陰離子產物,其中動力學效應可能會導緻F-的生成.
이론연구료간기부리자(OH-)여불록대갑완(CH2CIF)반응적음리자산물통도.분별재B3LYP/6-31+G(d,p)화B3LYP/6-311++G(2d,p)수평상득도반응세능면상각관건물충적우화구형,진이계산득도해진빈솔화영점능.기우CCSD(T)/6-311+G(3df,3dp)수평적상대능량,묘술료유질자전이화쌍분자친핵취대(SN2)과정생성각음리자산물적도경.각음리자산물도경세루적계산결과표명질자전이과정시실험중적주요산물통도,여이왕실험측량적결론상부.차외,계산환현시쌍분자친핵취대과정득도료비전형적음리자산물,기중동역학효응가능회도치F-적생성.
The anionic production pathways involved in the reaction between hydroxide anion (OH-) and chlorofluoromethane (CH2CIF) were theoretically investigated. The optimized geometries of all the important species on the reaction potential energy surface were obtained at the B3LYP/6-31 +G(d,p) and B3LYP/6-311 ++ G(2d,p) levels. Consequently, harmonic vibrational frequencies and zero point energies (ZPEs) were calculated. Based on the relative energies of all the species that were calculated at the CCSD(T)/6-311 +G(3df,3dp) level, the anionic production channels for the H+-abstraction and the bimolecular nucleophilic substitution (SN2) reaction processes are elaborated upon. According to the calculated barrier heights for the production pathways, the H+-abstraction channel is dominant, which agrees very well with previous experimental conclusions. In addition, non-typical anionic products are suggested to form during the SN2 reaction processes where the serious dynamic effect probably causes the SN2 reaction process to produce F-.