The mechanism and kinetics for the reaction of propene(CH3CH=CH2) molecule with O(1D) atom were investigated theoretically. The electronic structure information of the potential energy surface(PES) was obtained at the B3LYP/6-311+G(d,p) level, and the single-point energies were refined by the multi-level MCG3-MPWB method. The calculated results show that O(1D) atom can attack CH3CH=CH2 via the barrierless insertion mechanism to form four energy-riched intermediates CH3C(OH)CH2(IM1), CH3CHCHOH(IM2), CH2OHCHCH2(IM3) and cyclo CH2OCHCH3(IM4), respectively, on the singlet PES. The branching ratios as well as the pressure and temperature dependence of various product channels for this multi-well reaction were predicted by variational transition-state and Rice-Ramsperger-Kassel-Marcus(RRKM) theories. The present results will be useful to gain a deep insight into the reaction mechanism and kinetics of CH3CH=CH2+O(1D) reaction.
WU Nan-nan, LIU Hong-xia, DUAN Xue-mei and LIU Jing-yao State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130021, P. R. China
We analyzed the properties and structures of the hydrogen-bonded complexes of tetrahydrofuran(THF) and water by means of experimental Raman spectra and ab initio calculations.The optimized geometries and vibrational frequencies of the neat THF molecule and its hydrogen-bonded complexes with water(THF/H2O) were calculated at the MP2/6-311+G(d,p) level of theory.We found that the intermolecular hydrogen bonds which are formed from the binary mixtures of the neat THF and water with different molar ratios could explain the changes in wavenumber position and linewidth very well.The combination of ab initio calculations and experimental Raman spectral data provides an insight into the hydrogen bonds leading to the concentration dependent changes in the spectral features.
