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Title: Oxidation pathways in the reaction of diacetylene with OH radicals.

Abstract

We present a portion of the potential energy surface of the reaction of diacetylene with OH radicals, calculated using RQCISD(T) and two basis set extrapolation schemes. Based on this surface, we performed calculations of the rate coefficients using an RRKM/master-equation formalism. After a small (1 kcal/mol) adjustment to the energy barrier of the association reaction, our calculated rate coefficients of the high-pressure limit agree very well with previous direct measurements. However, our calculations at high temperatures are considerably smaller than the values inferred in previous studies. The non-Arrhenius behavior and significant pressure dependence of the rate coefficients above 800 K is due to the competition between stabilization, abstraction and addition - elimination channels. At low temperatures, the reaction proceeds mostly to the addition products, as well as to CO and propargyl. Above 1200 K, direct hydrogen abstraction and production of H atoms become important.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
971913
Report Number(s):
ANL/CHM/CP-117671
TRN: US201005%%40
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Conference: 31st International Symposium on Combustion; Aug. 6, 2006 - Aug. 11, 2006; Heidelberg, Germany
Country of Publication:
United States
Language:
ENGLISH
Subject:
08 HYDROGEN; ATOMS; COMBUSTION; EXTRAPOLATION; HYDROGEN; OXIDATION; POTENTIAL ENERGY; PRESSURE DEPENDENCE; PRODUCTION; RADICALS; STABILIZATION

Citation Formats

Senosiain, J. P., Klippenstein, S. J., Miller, J. A., Chemistry, and SNL. Oxidation pathways in the reaction of diacetylene with OH radicals.. United States: N. p., 2007. Web. doi:10.1016/j.proci.2006.08.084.
Senosiain, J. P., Klippenstein, S. J., Miller, J. A., Chemistry, & SNL. Oxidation pathways in the reaction of diacetylene with OH radicals.. United States. doi:10.1016/j.proci.2006.08.084.
Senosiain, J. P., Klippenstein, S. J., Miller, J. A., Chemistry, and SNL. Mon . "Oxidation pathways in the reaction of diacetylene with OH radicals.". United States. doi:10.1016/j.proci.2006.08.084.
@article{osti_971913,
title = {Oxidation pathways in the reaction of diacetylene with OH radicals.},
author = {Senosiain, J. P. and Klippenstein, S. J. and Miller, J. A. and Chemistry and SNL},
abstractNote = {We present a portion of the potential energy surface of the reaction of diacetylene with OH radicals, calculated using RQCISD(T) and two basis set extrapolation schemes. Based on this surface, we performed calculations of the rate coefficients using an RRKM/master-equation formalism. After a small (1 kcal/mol) adjustment to the energy barrier of the association reaction, our calculated rate coefficients of the high-pressure limit agree very well with previous direct measurements. However, our calculations at high temperatures are considerably smaller than the values inferred in previous studies. The non-Arrhenius behavior and significant pressure dependence of the rate coefficients above 800 K is due to the competition between stabilization, abstraction and addition - elimination channels. At low temperatures, the reaction proceeds mostly to the addition products, as well as to CO and propargyl. Above 1200 K, direct hydrogen abstraction and production of H atoms become important.},
doi = {10.1016/j.proci.2006.08.084},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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