A High Temperature Experimental and Theoretical Study of the Unimolecular Dissociation of 1,3,5-Trioxane

Handle URI:
http://hdl.handle.net/10754/553022
Title:
A High Temperature Experimental and Theoretical Study of the Unimolecular Dissociation of 1,3,5-Trioxane
Authors:
Alquaity, Awad B. S.; Giri, Binod Raj; Lo, John M.H.; Farooq, Aamir ( 0000-0001-5296-2197 )
Abstract:
Unimolecular dissociation of 1,3,5-trioxane was investigated experimentally and theoretically over a wide range of conditions. Experiments were performed behind reflected shock waves over the temperature range of 775-1082 K and pressures near 900 Torr using a high-repetition rate time of flight mass spectrometer (TOF-MS) coupled to a shock tube (ST). Reaction products were identified directly, and it was found that formaldehyde is the sole product of 1,3,5-trioxane dissociation. Reaction rate coefficients were extracted by the best fit to the experimentally measured concentration-time histories. Additionally, high-level quantum chemical and RRKM calculations were employed to study the falloff behavior of 1,3,5-trioxane dissociation. Molecular geometries and frequencies of all species were obtained at the B3LYP/cc-pVTZ, MP2/cc-pVTZ, and MP2/aug-cc-pVDZ levels of theory, whereas the single-point energies of the stationary points were calculated using coupled cluster with single and double excitations including the perturbative treatment of triple excitation (CCSD(T)) level of theory. It was found that the dissociation occurs via a concerted mechanism requiring an energy barrier of 48.3 kcal/mol to be overcome. The new experimental data and theoretical calculations serve as a validation and extension of kinetic data published earlier by other groups. Calculated values for the pressure limiting rate coefficient can be expressed as log<inf>10</inf> k<inf>∞</inf> (s-1) = [15.84 - (49.54 (kcal/mol)/2.3RT)] (500-1400 K). © 2015 American Chemical Society.
KAUST Department:
Clean Combustion Research Center; Physical Sciences and Engineering (PSE) Division
Citation:
A High Temperature Experimental and Theoretical Study of the Unimolecular Dissociation of 1,3,5-Trioxane 2015:150515134058009 The Journal of Physical Chemistry A
Publisher:
American Chemical Society (ACS)
Journal:
The Journal of Physical Chemistry A
Issue Date:
15-May-2015
DOI:
10.1021/acs.jpca.5b01801
Type:
Article
ISSN:
1089-5639; 1520-5215
Additional Links:
http://pubs.acs.org/doi/abs/10.1021/acs.jpca.5b01801
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorAlquaity, Awad B. S.en
dc.contributor.authorGiri, Binod Rajen
dc.contributor.authorLo, John M.H.en
dc.contributor.authorFarooq, Aamiren
dc.date.accessioned2015-05-17T20:45:19Zen
dc.date.available2015-05-17T20:45:19Zen
dc.date.issued2015-05-15en
dc.identifier.citationA High Temperature Experimental and Theoretical Study of the Unimolecular Dissociation of 1,3,5-Trioxane 2015:150515134058009 The Journal of Physical Chemistry Aen
dc.identifier.issn1089-5639en
dc.identifier.issn1520-5215en
dc.identifier.doi10.1021/acs.jpca.5b01801en
dc.identifier.urihttp://hdl.handle.net/10754/553022en
dc.description.abstractUnimolecular dissociation of 1,3,5-trioxane was investigated experimentally and theoretically over a wide range of conditions. Experiments were performed behind reflected shock waves over the temperature range of 775-1082 K and pressures near 900 Torr using a high-repetition rate time of flight mass spectrometer (TOF-MS) coupled to a shock tube (ST). Reaction products were identified directly, and it was found that formaldehyde is the sole product of 1,3,5-trioxane dissociation. Reaction rate coefficients were extracted by the best fit to the experimentally measured concentration-time histories. Additionally, high-level quantum chemical and RRKM calculations were employed to study the falloff behavior of 1,3,5-trioxane dissociation. Molecular geometries and frequencies of all species were obtained at the B3LYP/cc-pVTZ, MP2/cc-pVTZ, and MP2/aug-cc-pVDZ levels of theory, whereas the single-point energies of the stationary points were calculated using coupled cluster with single and double excitations including the perturbative treatment of triple excitation (CCSD(T)) level of theory. It was found that the dissociation occurs via a concerted mechanism requiring an energy barrier of 48.3 kcal/mol to be overcome. The new experimental data and theoretical calculations serve as a validation and extension of kinetic data published earlier by other groups. Calculated values for the pressure limiting rate coefficient can be expressed as log<inf>10</inf> k<inf>∞</inf> (s-1) = [15.84 - (49.54 (kcal/mol)/2.3RT)] (500-1400 K). © 2015 American Chemical Society.en
dc.publisherAmerican Chemical Society (ACS)en
dc.relation.urlhttp://pubs.acs.org/doi/abs/10.1021/acs.jpca.5b01801en
dc.rightsThis document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry A, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/acs.jpca.5b01801.en
dc.titleA High Temperature Experimental and Theoretical Study of the Unimolecular Dissociation of 1,3,5-Trioxaneen
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalThe Journal of Physical Chemistry Aen
dc.eprint.versionPost-printen
dc.contributor.institutionDepartment of Chemistry, University of Calgary, Cal gary, AB T2L 2K8, Canadaen
kaust.authorGiri, Binoden
kaust.authorFarooq, Aamiren
kaust.authorAlquaity, Awaden
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