Competing Nonadiabatic Relaxation Pathways for Near-UV Excited ortho-Nitrophenol in Aqueous Solution DOI Creative Commons
Hallam J. M. Greene, Deborin Ghosh, Igor V. Sazanovich

et al.

The Journal of Physical Chemistry Letters, Journal Year: 2024, Volume and Issue: 15(36), P. 9153 - 9159

Published: Aug. 29, 2024

Nitrophenols are atmospheric pollutants found in brown carbon aerosols produced by biomass burning. Absorption of solar radiation these nitrophenols contributes to radiative forcing, but quantifying this climate impact requires better understanding their photochemical pathways. Here, the photochemistry near-UV (λ = 350 nm) excited ortho-nitrophenol aqueous solution is investigated using transient absorption spectroscopy and time-resolved infrared over fs μs time scale characterize states, intermediates, photoproducts. Interpretation data supported quantum chemical calculations linear-response time-dependent density functional theory (LR-TDDFT). Our results indicate efficient nonradiative decay via an S1(ππ*)/S0 conical intersection leading hot ground state which vibrationally cools solution. A previously unreported minor pathway involves intersystem crossing near S1(nπ*) minimum, with resulting triplet facilitated deprotonation. These relaxation pathways account for low yields photodegradation.

Language: Английский

Competing Nonadiabatic Relaxation Pathways for Near-UV Excited ortho-Nitrophenol in Aqueous Solution DOI Creative Commons
Hallam J. M. Greene, Deborin Ghosh, Igor V. Sazanovich

et al.

The Journal of Physical Chemistry Letters, Journal Year: 2024, Volume and Issue: 15(36), P. 9153 - 9159

Published: Aug. 29, 2024

Nitrophenols are atmospheric pollutants found in brown carbon aerosols produced by biomass burning. Absorption of solar radiation these nitrophenols contributes to radiative forcing, but quantifying this climate impact requires better understanding their photochemical pathways. Here, the photochemistry near-UV (λ = 350 nm) excited ortho-nitrophenol aqueous solution is investigated using transient absorption spectroscopy and time-resolved infrared over fs μs time scale characterize states, intermediates, photoproducts. Interpretation data supported quantum chemical calculations linear-response time-dependent density functional theory (LR-TDDFT). Our results indicate efficient nonradiative decay via an S1(ππ*)/S0 conical intersection leading hot ground state which vibrationally cools solution. A previously unreported minor pathway involves intersystem crossing near S1(nπ*) minimum, with resulting triplet facilitated deprotonation. These relaxation pathways account for low yields photodegradation.

Language: Английский

Citations

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