SiH_3自由基与NO反应机理的理论研究

Theoretical Study on the Reaction Mechanism of SiH_3 with NO

采用密度泛函B3LYP/6-311G++(d,p)和高级电子相关耦合簇CCSD(T)/6-311G++(d,p)方法研究了SiH3与NO在单重态势能面上的反应机理,全参数优化了反应势能面上的各驻点的几何构型,用内禀反应坐标(IRC)对过渡态进行了验证.找到以下反应路径R→IM01→TS01→P1(HSiNO+H2);R→IM01→TS02→IM02→TS03→IM04→TS06→P2(HSiN+H2O),产物P2经过1-2位氢迁移转化为最稳定的产物P3(HNSi+H2O);R→IM01→TS11→IM06→TS16→IM10→TS17→P4(HSiON+H2);R→IM01→TS11→IM06→TS18→P5(H2SiONH);R→IM01→TS11→IM06→TS19→P6(HSiONH2)等.

The reactions of silyl radicals with nitric oxide, SiH3 ＋ NO, were carried out at the DFT/ B3LYP/6-311G＋ ＋（d,p） level of theory and the high-level electron-correlation method CCSD（T）/6-311G＋＋（d,p） on singlet potential energy surface （PES）. The geometries of the reactants, transition states and products were completely optimized. All the transition states were verified by vibrational analysis and internal reaction coordinate （IRC） calculations. The reaction pathway is as follows： R→IM01→TS01→P1 （HSiNO＋H2） ; R→IM01→TS02→IM02→TS03→IM04→TS06→P2 （HSiN＋ H2O）. The product P2（HSiN＋H2O） can produce the most stable product P3 （HNSi＋H2O） via a 1,2-hydrogen shift; R→IM01→ TS11 → IM06 → TS16 → IM10 → TS17 → P4 （ HSiON ＋ H2 ） ; R→ IM01→ TS11 → IM06 → TS18 → P5（H2SiONH） ; R→IM01→TS11→IM06→TS19→P6 （ HSiONH2 ） etc.