The decisive role of pericyclic reactions in the thermal decomposition of organophosphorus compounds
| Autor: | Pierre-Alexandre Glaude, L. Verdier, René Fournet, Baptiste Sirjean, J.-C. Lizardo-Huerta |
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| Přispěvatelé: | Laboratoire Réactions et Génie des Procédés (LRGP), Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL), Délégation générale de l'armement (DGA), Ministère de la Défense |
| Rok vydání: | 2021 |
| Předmět: |
Organophosphorus compounds
Pericyclic reaction DIMP General Chemical Engineering 010402 general chemistry 01 natural sciences theoretical chemistry sarin [SPI]Engineering Sciences [physics] Transition state theory chemistry.chemical_compound Reaction rate constant Computational chemistry 0103 physical sciences Molecule Physical and Theoretical Chemistry DEMP Triethyl phosphate 010304 chemical physics Chemistry Mechanical Engineering Thermal decomposition modeling Phosphonate Decomposition 0104 chemical sciences [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry TEP chemical warfare agents |
| Zdroj: | Proceedings of the Combustion Institute Proceedings of the Combustion Institute, Elsevier, 2021, 38 (1), pp.719-727. ⟨10.1016/j.proci.2020.08.007⟩ |
| ISSN: | 1540-7489 |
| DOI: | 10.1016/j.proci.2020.08.007 |
| Popis: | International audience; The understanding of the thermal decomposition chemistry of chemical warfare nerve agents is largely limited by the scarcity of kinetic data. Because of the high toxicity of these molecules, experimental determination of their chemical properties is very difficult. In the present work, a comprehensive detailed kinetic model for the decomposition of sarin and some simulants, i.e. di-isopropyl methyl phosphonate (DIMP), diethyl methylphosphonate (DEMP), and triethyl phosphate (TEP) were developed, containing possible molecular and radical pathways. The importance of unimolecular pericyclic decomposition led to evaluate precisely the rate constants of these reactions with high level theoretical calculations. The QCISD(T)/cc-PV∞QZ//B2PLYPD3/6-311+G(2d,d,p) level of theory was selected after a benchmark. The contribution of hindered rotors was included with the 1D-HR-U approach. Tunneling was taken into account for H-atom transfer. Transition state theory was used to calculate high-pressure limit rate constants and pressure dependent rate constants were calculated using Master Equation modelling. The model was validated against experimental pyrolysis and oxidation experimental data available in literature. Flux analyses showed that whatever the conditions are, the first step of decomposition of the studied phosphorus compounds are pericyclic eliminations leading to successive decompositions, whereas bondbreaking or H-atom abstraction remain negligible, even at high temperature. |
| Databáze: | OpenAIRE |
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