Articles | Volume 19, issue 12
https://doi.org/10.5194/amt-19-3961-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-19-3961-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Jun 2026
Research article |
| 17 Jun 2026
| 17 Jun 2026
Measuring molecular singlet oxygen (1O2*) from atmospheric photosensitizers: Intercomparison of techniques, irradiation setups, data analysis and protocol recommendations
Keighan J. Gemmell
Department of Chemistry, University of British Columbia, Vancouver, V6T 1Z1, Canada
Laura Marie Dahler Heinlein
Department of Land, Air and Water Resources, University of California, Davis, CA 95616, USA
Emma A. Petersen-Sonn
Universite Claude Bernard Lyon 1, CNRS, IRCELYON, UMR 5256, Villeurbanne, 69100, France
Claudia Sardena
Department of Chemistry, University of British Columbia, Vancouver, V6T 1Z1, Canada
Zhongyu Guo
Universite Claude Bernard Lyon 1, CNRS, IRCELYON, UMR 5256, Villeurbanne, 69100, France
Nory Mariño-Ocampo
Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
Belinda Heyne
Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
Christian George
Universite Claude Bernard Lyon 1, CNRS, IRCELYON, UMR 5256, Villeurbanne, 69100, France
Cort Anastasio
Department of Land, Air and Water Resources, University of California, Davis, CA 95616, USA
Nadine Borduas-Dedekind
CORRESPONDING AUTHOR
Department of Chemistry, University of British Columbia, Vancouver, V6T 1Z1, Canada
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Short summary
Molecular singlet oxygen (1O2*) is the first excited state of O2 and is produced when sunlight excites light-absorbing molecules in aerosols in the atmosphere. 1O2* can drive oxidation reactions and impact aerosol properties. This study is an inter-comparison of photoreactors, light sources and data analysis across 3 atmospheric chemistry laboratories, yielding a critical assessment of practices and recommendations for intercomparing 1O2* measurements and extrapolating to ambient particles.
Molecular singlet oxygen (1O2*) is the first excited state of O2 and is produced when sunlight...
