Reactions of hydrazine with the amidogen radical and atomic hydrogen |
| |
| Institution: | 1. Department of Chemistry and Center for Advanced Scientific Computing and Modeling, University of North Texas, 1155 Union Circle #305070, Denton, TX 76203, USA;2. Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark;1. Key Laboratory for Power Machinery and Engineering of MOE, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China;2. Clean Combustion Research Center, King Abdullah University of Science and Technology, Thuwal, 23955, Kingdom of Saudi Arabia;1. UFR Sciences et Techniques, Université d''Orléans, rue de Chartres, 45100 Orléans, France;2. CNRS–ICARE, 1C avenue de la Recherche Scientifique, 45071 Orléans cedex 2, France;1. Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, 2800 Kgs. Lyngby, Denmark;2. Sino-Danish College, University of Chinese Academy of Sciences, Eastern Yanqihu campus, 380 Huaibeizhuang, Huairou district, Beijing, 101400, China;3. Sino-Danish Center for Education and Research, Eastern Yanqihu campus, 380 Huaibeizhuang, Huairou district, Beijing, 101400, China;4. Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Kemigården 4, 412 96 Gothenburg, Sweden;1. School of Chemistry and Chemical Engineering, Hubei Key Laboratory of Coal Conversion and New Carbon Materials, Wuhan University of Science and Technology, Wuhan, Hubei 430081, China;2. Department of Energy Conversion Engineering, Wroc?aw University of Science and Technology, Wroc?aw 50-370, Poland;3. Department of Chemical and Biochemical Engineering, Technical University of Denmark, Kgs. Lyngby 2800, Denmark;4. State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;5. University of Chinese Academy of Sciences, Beijing 100049, China |
| |
| Abstract: | The rate coefficient k1 for NH2 + N2H4 was measured to be (5.4 ± 0.4) × 10?14 cm3 molecule?1 s?1 at 296 K. NH2 was generated by pulsed laser photolysis of NH3 at 193 nm, and monitored as a function of time by pulsed laser-induced fluorescence excited at 570.3 nm under pseudo-first order conditions in the presence of excess N2H4 in an Ar bath gas. This reaction was also investigated computationally, with geometries and scaled frequencies obtained with M06-2X/6-311+G(2df,2p) theory, and single-point energies from CCSD(T)-F12b/cc-pVTZ-F12 theory, plus a term to correct approximately for electron correlation through CCSDT(Q). Three connected transition states are involved and rate constants were obtained via Multistructural Improved Canonical Variational Transition State Theory with Small Curvature Tunneling. Combination of experiment and theory leads to a recommended rate coefficient for hydrogen abstraction of k1 = 6.3 × 10?23 T3.44 exp(+289 K/T) cm3 molecule?1 s?1. The minor channel for H + N2H4 forming NH2 + NH3 was characterized computationally as well, to yield 5.0 × 10?19 T2.07 exp(-4032 K/T) cm3 molecule?1 s?1. These results are compared to several discordant prior estimates, and are employed in an overall mechanism to compare with measurements of half-lives of hydrazine in a shock tube. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
