XCOOH(X=F,Cl,Br)热分解反应的理论研究

Thermodynamic study on the reactions of XCOO H(X=F,Cl,Br) HX+CO_2

用密度泛函理论(DFT)B3LYP方法,在6 311+G 基组水平上,计算了反应XCOOH(X=F,Cl,Br)HX+CO2.优化了反应物 中间体 过渡态和产物的几何构型,并用频率分析和内禀坐标法(IRC)验证了各鞍点构型和反应路径,计算了不同温度(200 15～450 15K)下慢反应经零点能校正的活化热力学量、反应过程热力学改变量、正逆反应的速率常数和频率因子以及平衡常数,得到了各反应的动力学信息.

The reactions of XCOO H(X=F,Cl,Br) HX + CO2 have been studied using the density functional metho d(DFT) at B3L YP(full)/6-311 +G-(**_ level. The energies and structures of reactants, productions, intermediates and transition states are optimized in full geometries, the transition states are found by the EF.method and proved by frequency analysis and IRC calculations. The slow reactions activation thermodynamic data are calculated based on the transition states theory, and the rate constants,frequency factors and reaction equilibrium constants are obtained from 200.15 K to 450.15 K,at the same time,some dynamical results are obtained.