Gas-phase rate coefficient of OH + cyclohexene oxide measured from 251 to 373 K

Hajar El Othmani (1, 2, 3) , Yangang Ren (1, 2) , Wahid Mellouki (1, 2) , Véronique Daële (1, 2) , Max Mcgillen (1, 2)

1 ICARE - Institut de Combustion, Aérothermique, Réactivité et Environnement
2 OSUC - Observatoire des Sciences de l'Univers en région Centre
3 UM5 - Université Mohammed V de Rabat [Agdal]

Absolute measurements of the rate coefficient of the title reaction are reported from 251 to 373 K using the laser-induced fluorescence–pulsed-laser photolysis technique, together with room-temperature relative rate determinations using a simulation chamber. These are the first reported values of this rate coefficient, which demonstrates a predominantly negative temperature dependence that is more pronounced than with other epoxides, suggesting that pre-reactive complexes contribute to the overall reactivity, and that these complexes are comparatively stable for OH + cyclohexene oxide, which may result from its bicyclic structure. This work provides new insights into the lesser-studied reactivity of the epoxide functionality.

Mots clés: Epoxide; Oxirane; Hydroxyl Atmospheric chemistry; Kinetics Rate constant

Domaines: Planète et Univers [physics]

Hajar El Othmani, Yangang Ren, Wahid Mellouki, Véronique Daële, Max Mcgillen. Gas-phase rate coefficient of OH + cyclohexene oxide measured from 251 to 373 K. Chemical Physics Letters, 2021, 783, pp.139056. ⟨10.1016/j.cplett.2021.139056⟩. ⟨insu-03352180⟩