On the role of molecular clustering on infrared absorption line shapes of acetylene in a supersonic expansion
نویسندگان
چکیده
A supersonic expansion containing acetylene seeded into Ar and produced from a circular nozzle is investigated using CW/cavity ring down spectroscopy, in the 1.5 lm range. The results, also involving experiments with pure acetylene and acetylene-He expansions, as well as slit nozzles, demonstrate that the denser central section in the expansion is slightly heated by the formation of acetylene aggregates, resulting into a dip in the monomer absorption line profiles. Acetylene–Ar aggregates are also formed at the edge of the circular nozzle expansion cone. 2008 Elsevier B.V. All rights reserved.
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