Publication: Quenching of ketone triplet excited states by atmospheric halides
Publication - Quenching of ketone triplet excited states by atmospheric halides
Quenching of ketone triplet excited states by atmospheric halides
Publication Year: 2021
Author list: Gemayel R., Emmelin C., Perrier S., Tomaz S., Baboomian V. J., Fishman D. A., Nizkorodov S. A., Dumas S., George C.
Journal Short Name: Environmental Science: Atmospheres
Publisher: Royal Society of Chemistry
AbstractThe photosensitized chemistry of three aromatic ketones (xanthone, flavone, and acetophenone) and also of secondary organic aerosol (SOA) arising from the photo-oxidation of naphthalene was investigated by means of transient absorption spectroscopy. Halide ions were selected to probe the reactivity of the generated triplet states. The quenching rate constants ranged from 109M1s1with iodide ions to less than 105M1s1with chloride ions. The halide-triplet state interactions produced the corresponding radical anion (X2c) along with halogenated and more oxidized organic compounds as identified by liquid chromatography and mass spectrometry. Deoxygenated naphthalene SOA solutions showed strong transient absorption at 420 nm when excited at 355 nm, and were also quenched by iodide ions similar to the single compound experiments indicating that compounds in naphthalene SOA can act as photosensitizers. Combining the study of these individual and known photosensitizers with those formed in the atmosphere (in this case through the oxidation of naphthalene) demonstrates that tropospheric photosensitization may involve a large variety of compounds of primary or secondary nature and will introduce new, unconsidered chemical pathways that impact atmospheric multiphase chemistry.
|ID||Name||Start date||Experiment Category||Reaction Type||Reactant(s)||Oxidant Name||Temperature||Humidity||Type of Seed||RO2 Main Fate||Data Sets (count)||Actions|
|527||Nizkorodov Lab_20180618_naphthalene/nitric oxide_Hydroxyl radical_No Seed_Nizkorodov Lab_20180615_naphthalene/nitric oxide_Hydroxyl radical_No Seed_clone||2018-06-18||Aerosol formation||Photooxidation||naphthalene, nitric oxide||Hydroxyl radical||21.1||40||RO2||2|
|528||Nizkorodov Lab_20180619_naphthalene/nitric oxide_Hydroxyl radical_No Seed_Nizkorodov Lab_20180618_naphthalene/nitric oxide_Hydroxyl radical_No Seed_Nizkorodov Lab_20180615_naphthalene/nitric oxide_Hydroxyl radical_No Seed_clone_clone||2018-06-19||Aerosol formation||Photooxidation||naphthalene, nitric oxide||Hydroxyl radical||21.1||40||RO2||2|