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arXiv · 1708.04114

How Do Methyl Groups Enhance the Triplet Chemiexcitation Yield of Dioxetane?

Morgane Vacher·Pooria Farahani·Alessio Valentini·Luis Manuel Frutos·Hans O. Karlsson·Ignacio Fdez. Galván·Roland Lindh
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Abstract

Chemiluminescence is the emission of light as a result of a nonadiabatic chemical reaction. The present work is concerned with understanding the yield of chemiluminescence, in particular how it dramatically increases upon methylation of 1,2-dioxetane. Both ground-state and nonadiabatic dynamics (including singlet excited states) of the decomposition reaction of various methyl-substituted dioxetanes have been simulated. Methyl-substitution leads to a significant increase in the dissociation time scale. The rotation around the O-C-C-O dihedral angle is slowed; thus, the molecular system stays longer in the "entropic trap" region. A simple kinetic model is proposed to explain how this leads to a higher chemiluminescence yield. These results have important implications for the design of efficient chemiluminescent systems in medical, environmental, and industrial applications.

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Morgane Vacher, Pooria Farahani, Alessio Valentini, Luis Manuel Frutos, Hans O. Karlsson, Ignacio Fdez. Galván, Roland Lindh. 2017-08-10. How Do Methyl Groups Enhance the Triplet Chemiexcitation Yield of Dioxetane?. https://doi.org/10.1021/acs.jpclett.7b01668

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