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Title: Effect of CH stretching excitation on the reaction dynamics of F + CHD{sub 3} → DF + CHD{sub 2}

The vibrationally excited reaction of F + CHD{sub 3}(ν{sub 1} = 1) → DF + CHD{sub 2} at a collision energy of 9.0 kcal/mol is investigated using the crossed-beams and time-sliced velocity map imaging techniques. Detailed and quantitative information of the CH stretching excitation effects on the reactivity and dynamics of the title reaction is extracted with the help of an accurate determination of the fraction of the excited CHD{sub 3} reagent in the crossed-beam region. It is found that all vibrational states of the CHD{sub 2} products observed in the ground-state reaction, which mainly involve the excitation of the umbrella mode of the CHD{sub 2} products, are severely suppressed by the CH stretching excitation. However, there are four additional vibrational states of the CHD{sub 2} products appearing in the excited-state reaction which are not presented in the ground-state reaction. These vibrational states either have the CH stretching excitation retained or involve one quantum excitation in the CH stretching and the excitation of the umbrella mode. Including all observed vibrational states, the overall cross section of the excited-state reaction is estimated to be 66.6% of that of the ground-state one. Experimental results also show that when the energy of CHmore » stretching excitation is released during the reaction, it is deposited almost exclusively as the rovibrational energy of the DF products, with little portion in the translational degree of freedom. For vibrational states of the CHD{sub 2} products observed in both ground- and excited-state reactions, the CH stretching excitation greatly suppresses the forward scattered products, causing a noticeable change in the product angular distributions.« less
Authors:
; ; ;  [1] ;  [2] ; ; ; ;  [1] ;  [3]
  1. State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian, Liaoning 116023 (China)
  2. Dynamics at Surfaces, Faculty of Chemistry, Georg-August-Universität Göttingen, 37077 Göttingen (Germany)
  3. (China)
Publication Date:
OSTI Identifier:
22493464
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ANGULAR DISTRIBUTION; CROSS SECTIONS; DEGREES OF FREEDOM; DEUTERIUM COMPOUNDS; EXCITATION; EXCITED STATES; FLUORIDES; FLUORINE; GROUND STATES; HYDROCARBONS; REACTIVITY; REAGENTS; VELOCITY; VIBRATIONAL STATES