Source:http://linkedlifedata.com/resource/pubmed/id/16229576
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
7
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| pubmed:dateCreated |
2005-10-18
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| pubmed:abstractText |
The structures and energies of the reactants, products, and transition states of the initial steps in the gas-phase decomposition of dimethylnitramine (DMNA) have been determined by quantum chemical calculations at the B3LYP density-functional theory, MP2, and G2 levels. The pathways considered are NO2 elimination, HONO elimination, and nitro-nitrite rearrangement. The NO2 elimination is predicted to be the main channel of the gas-phase decomposition of DMNA in accord with experiment. The values of the Arrhenius parameters, log A=16.6+/-0.5 and Ea=40.0+/-0.6 kcal/mol, for the N-NO2 bond-fission reaction were obtained using a canonical variational theory with B3LYP energies and frequencies. The HONO-elimination channel has the next lowest activation energy of 44.7+/-0.5 kcal/mol (log A=13.6+/-0.5) and is characterized by a five-member transition-state configuration in which a hydrogen atom from one of the methyl groups is transferred to an oxygen atom of NO2. Tunneling contributions to the rate of this reaction have been estimated. The nitro-nitrite rearrangement reaction occurs via a transition state in which both oxygen atoms of NO2 are loosely bound to the central nitrogen atom, for which Rice-Ramsperger-Kassel-Marcus theory predicts log A=14.4+/-0.6 and Ea=54.1+/-0.8 kcal/mol.
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:status |
PubMed-not-MEDLINE
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| pubmed:month |
Aug
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| pubmed:issn |
0021-9606
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| pubmed:author | |
| pubmed:issnType |
Print
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| pubmed:day |
15
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| pubmed:volume |
123
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
074313
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| pubmed:year |
2005
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| pubmed:articleTitle |
Theoretical predictions of the initial decomposition steps of dimethylnitramine.
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| pubmed:affiliation |
Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211, USA.
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| pubmed:publicationType |
Journal Article
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