MoS^+和COS气相反应的理论研究  

Theoretical Study on Reaction of MoS^+ with COS in Gas Phase

作　　者：杨树[1,2] 杨晓梅 谢小光[2] 

机构地区：[1]云南大学化学科学与工程学院,云南昆明650091 [2]昆明理工大学理学院,云南昆明650500 [3]云南中医药大学,云南昆明650500

出　　处：《昆明理工大学学报（自然科学版）》2012年第6期76-84,共9页Journal of Kunming University of Science and Technology(Natural Science)

基　　金：国家自然科学基金(20563005)

摘　　要：采用密度泛函B3LYP方法,研究了MoS+(4-、2Δ)和SCO在气相中的反应:氧/硫交换反应(MoS++COS→MoO++CS2),氧转移反应(MoS++COS→SMoO++CS)和硫转移反应(MoS++COS→MoS2++CO).对反应势能面上各驻点的几何构型进行了全优化,用频率分析方法和内禀反应坐标(IRC)方法对过渡态进行了验证.对影响反应机理的势能面交叉现象进行了讨论,运用Hammond假设和Yoshizawa等的内禀反应坐标垂直激发的计算方法找到了势能面交叉点.确定了四重态和二重态的反应机理和能量.计算结果表明C-S键比C-O键的活化在能量上更占优势.计算结果与实验吻合.The reactions of MoS＋（4∑-,2Δ） with COS in gas phase are studied using density functional theory at the B3LYP level：the O/S exchange reaction（MoS＋ ＋ COS →MoO＋ ＋ CS2）,the O-transfer reaction（MoS＋ ＋ COS →SMoO＋ ＋ CS） and the S-transfer reaction（MoS＋ ＋ COS →MoS＋2 ＋ CO）.The geometries of transition states on the potential energy surface are fully optimized.All the transition states are then verified by the vibrational analysis and the intrinsic reaction coordinate（IRC） calculations.The involved potential energy curve-crossing dramatically affecting reaction mechanism is elaborated.The crossing points are localized by means of the Hammond postulate and the intrinsic reaction coordinate approach suggested by Yoshzawa et al.The different mechanisms and energy on the quartet and doublet surfaces are also identified.The results show that the C-S bond activation is much favorable than the C-O bond activation in energy.The theoretical results are in line with experiments.

关 键 词：密度泛函理论 硫化钼离子 反应机理 

分 类 号：O643[理学—物理化学]