异硫氰酸与GeF_2自由基反应机理的理论研究

Theoretical Study of the Reaction Mechanism for Isothiocyanic Acid with GeF_2 Radical

为了研究异硫氰酸与单重态GeF2自由基的反应机理,采用密度泛函理论(DFT)的B3LYP方法和二次组态相互作用方法[QCISD(T)]及电子密度拓扑分析(AIM)和自然键轨道理论(NBO)方法.在B3LYP/6-311++G**水平上对反应势能面上各驻点进行全几何参数优化,又在QCISD(T)/6-311++G**水平上计算各个驻点的相对能量.计算结果表明单重态的GeF2自由基与异硫氰酸反应有2条可能的反应通道.其中反应通道GeF2+HNCS→IM1→TS1→HGeF2SCN(P1)为主反应通道.

The reaction mechanism of Isothiocyanic Acid with GeF2 radical of the singlet has been investigated in a B3LYP method of density functional theory, QCISD （T） method, natural bond orbital （NBO） theory and topological analysis of electronic density. The geometries and harmonic vibration frequencies have been calculated at the B3LYP/6-311＋＋G^＊＊ level. And the stationary point energies were calculated at a QCISD （T）/6 - 311 ＋＋G^＊＊//B3LYP/6 - 311＋＋G^＊＊ level. The calculated results show that the addition reaction pathways of the singlet GeF2 reacting with HNCS involve two feasible reaction pathways and the reaction GeF2 ＋ HNCS→ IM1 →TS1→HGeF2NCS（P1） was the main pathway.