Chemical Lasers Produced from O(3P) Atom Reactions. II. a Mechanistic Study of 5-μm CO Laser Emission from the O + C2H2 Reaction

  • M. C. Lin


The reaction of O(3P) atoms with C2H2 has been the subject of many investigations. At low temperatures, the mechanism of CO formation, studied by a variety of methods,1–6 is now generally accepted as7
$$O + {C_2}{H_2} \to CO\dag + C{H_2} + 47kcal/mole$$
$$O + C{H_2} \to CO\dag + 2H + 75kcal/mole$$
Other minor reactions yielding HC2O and C2O are also believed to occur.5 IR chemiluminescence experiments have been performed independently by Creek et al.8 and by Thrush and co-workers9 employing low-pressure, fast-flow methods. At low C2H2 concentrations, the distribution of CO extends to v’=14, which is attributed to reactions (1) and (2).8,9 Additional distribution extending up to v’≈33 was detected at high C2H2 flows and in the presence of H2. This is believed to be due to reaction (3),9
$$O + CH \to CO\dag + H + 176kcal/mole$$
Other processes such as:
$$O + CH \to CO \uparrow + H + 176kcal/mole$$
$$2O + {C_2}{H_2} \to O + \left[ {{C_2}{H_2}O} \right]* \to 2CO \uparrow + 2H + 122kcal/mole$$
have also been proposed to account for the production of CO in high vibrational levels.5,8


Laser Emission Hydrogen Halide Chemical Laser High Vibrational Level Methyl Acetylene 
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Copyright information

© Springer Science+Business Media New York 1973

Authors and Affiliations

  • M. C. Lin
    • 1
  1. 1.Naval Research LaboratoryUSA

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