XNCS→XSCN(X=Cl,Br)异构化的实验与量子化学研究

Experimental and Quantum Chemical Study on XNCS to XSCN (X=Cl, Br) Isomerization Reactions

捕获得到了纯净化合物ClSCN和BrSCN紫外光电子能谱图 ,OVGF方法计算的ClSCN和BrSCN的电离能与实验值吻合很好 ,并用该方法首次预测了ClNCS和BrNCS的电离能 .讨论了XNCS→XSCN (X =Cl ,Br)的异构化过程 ,首次优化得到了四元环过渡态的构型 .着重从电子密度拓扑分析计算了反应进程中的各点 ,讨论了反应进程中键的断裂和生成 ,上述反应都经历了三元环过渡结构 ,找到了这类反应的“能量过渡态”和“结构过渡态”

The photoelectron spectra (PES) of ClSCN and BrSCN have been recorded and Outer Valence Green's Function (OVGF) calculations give quite good results in ionization potential energies. The ionization potential energies of ClNCS and BrNCS have been predicted by OVGF calculations. The isomerization reactions XNCS-->XSCN (X = cl, Br) have been computed by B3LYP/6-311 + + G(2df) and the four-membered ring transition states are optimized. The breakage and formation of the chemical bonds in the reactions have been discussed by the topological analysis method of electronic density, and the calculated results show that there is a transitional structure of three-membered ring on both of the isomerization reaction paths. The 'energy transition state' and the 'structure transition state' in both of the studied reactions have been found.