Experimental and Theoretical Investigation on the OH + CH3C(O)CH3 Reaction at Interstellar Temperatures (T = 11.7–64.4 K)
العنوان: | Experimental and Theoretical Investigation on the OH + CH3C(O)CH3 Reaction at Interstellar Temperatures (T = 11.7–64.4 K) |
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المؤلفون: | André Canosa, Daniel González, Bernabé Ballesteros, Elena Jiménez, José Albaladejo, Astrid Bergeat, Alberto García-Sáez, Raphaël Méreau, Françoise Caralp, María Antiñolo, Sergio Blázquez |
المساهمون: | Universidad de Castilla-La Mancha = University of Castilla-La Mancha (UCLM), Institut des Sciences Moléculaires (ISM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1 (UB)-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), European Research Council, ERC SyG-610256European Cooperation in Science and Technology, COST CM1401Universidad de Castilla-La Mancha, UCLMCentre National de la Recherche Scientifique, CNRS, Universidad de Castilla-La Mancha (UCLM), Université Montesquieu - Bordeaux 4-Université Sciences et Technologies - Bordeaux 1-École Nationale Supérieure de Chimie et de Physique de Bordeaux (ENSCPB)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS) |
المصدر: | ACS Earth Space Chem ACS Earth and Space Chemistry ACS Earth and Space Chemistry, 2019, 3 (9), pp.1873-1883. ⟨10.1021/acsearthspacechem.9b00144⟩ ACS Earth and Space Chemistry, ACS, 2019, 3 (9), pp.1873-1883. ⟨10.1021/acsearthspacechem.9b00144⟩ |
بيانات النشر: | American Chemical Society (ACS), 2019. |
سنة النشر: | 2019 |
مصطلحات موضوعية: | Atmospheric Science, gas-phase kinetics, Radical, Analytical chemistry, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, 7. Clean energy, Article, Chemical kinetics, Orders of magnitude (specific energy), Geochemistry and Petrology, Quantum tunnelling, ultralow temperatures, [PHYS]Physics [physics], Molecular cloud, CRESU, Pressure dependence, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Interstellar medium, interstellar molecules, 13. Climate action, Space and Planetary Science, Potential energy surface, Molecular physics, 0210 nano-technology |
الوصف: | International audience; The rate coefficient, k(T), for the gas-phase reaction between OH radicals and acetone CH3C(O)CH3, has been measured using the pulsed CRESU (French acronym for Reaction Kinetics in a Uniform Supersonic Flow) technique (T = 11.7-64.4 K). The temperature dependence of k(T = 10-300 K) has also been computed using a RRKM-Master equation analysis after partial revision of the potential energy surface. In agreement with previous studies we found that the reaction proceeds via initial formation of two prereactive complexes both leading to H2O + CH3C(O)CH2 by H-abstraction tunneling. The experimental k(T) was found to increase as temperature was lowered. The measured values have been found to be several orders of magnitude higher than k(300 K). This trend is reproduced by calculations, with an especially good agreement with experiments below 25 K. The effect of total gas density on k(T) has been explored. Experimentally, no pressure dependence of k(20 K) and k(64 K) was observed, while k(50 K) at the largest gas density 4.47 × 1017 cm-3 is twice higher than the average values found at lower densities. The computed k(T) is also reported for 103 cm-3 of He (representative of the interstellar medium). The predicted rate coefficients at 10 K surround the experimental value which appears to be very close to that of the low pressure regime prevailing in the interstellar medium. For gas-phase model chemistry of interstellar molecular clouds, we suggest using the calculated value of 1.8 × 10-10 cm3 molecule-1 s-1 at 10 K, and the reaction products are water and CH3C(O)CH2 radicals. © 2019 American Chemical Society. |
تدمد: | 2472-3452 |
URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4979bd05b2250cb28eb2d43309471e04 https://doi.org/10.1021/acsearthspacechem.9b00144 |
حقوق: | OPEN |
رقم الأكسشن: | edsair.doi.dedup.....4979bd05b2250cb28eb2d43309471e04 |
قاعدة البيانات: | OpenAIRE |
تدمد: | 24723452 |
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