CAJ | 학술논문

采用密度泛函理论B3LYP方法研究了硫化钇离子YS+(1Σ+,3φ)与硫转移试剂COS在气相中的反应:YS++COS→YS2++CO.在单重基态和三重激发态势能面上都找到了四条反应通道.但是除一条反应通道之外,其它的反应机理和几何结构变化趋势在不同的势能面上有很大不同.实验中生成YS2+所表现出的吸热特征来自于在基态反应中的三条通道(A,B和C),其活化势垒分别为28.3、140.5和120.2 kJ.mol-1.计算结果表明硫转移反应没有双态反应活性,因此产物YS2+在低能量区的放热特征是由于基态反应物中还混有残留的激发态YS+.
채용밀도범함이론B3LYP방법연구료류화을리자YS+(1Σ+,3φ)여류전이시제COS재기상중적반응:YS++COS→YS2++CO.재단중기태화삼중격발태세능면상도조도료사조반응통도.단시제일조반응통도지외,기타적반응궤리화궤하결구변화추세재불동적세능면상유흔대불동.실험중생성YS2+소표현출적흡열특정래자우재기태반응중적삼조통도(A,B화C),기활화세루분별위28.3、140.5화120.2 kJ.mol-1.계산결과표명류전이반응몰유쌍태반응활성,인차산물YS2+재저능량구적방열특정시유우기태반응물중환혼유잔류적격발태YS+.
The gas-phase reaction of YS+ (+Σ+,3φ) with an S-transfer reagent (COS),YS++COS→YS2++ CO,was studied using density functional theory at the B3LYP/6-311 + G* level.Four parallel reaction pathways were identified on both the ground- and excited-state surfaces.The mechanisms and the geometrical change trends on the different surfaces are quite different,except in the case of one reaction channel.The experimentally observed endothermic feature of the formation of YS2+ can be attributed to three reaction paths,A,B,and C,with calculation barriers of 28.3,140,5,and 120.2 kJ,mol-1,respectively,on the ground singlet surface.Our calculation results show that the title reaction has no two-state reactivity and the exothermic feature of the YS2+ cross-section observed in the experiments is attributed to reaction of the residual excited-state of YS+ in the reactants.