{
  "abstract": "Molecular singlet oxygen (1O∗2) is the first ex-cited state of molecular oxygen (O2) and can be formedthrough indirect photochemistry during irradiation of chromophoric organic matter. Once formed in the particle and droplet phases in the atmosphere, 1O∗2 can be a competitive oxidant in the photochemical processing of organic matter. Now, as more researchers study the atmospheric photo-chemistry of 1O∗2, establishing protocols by evaluating and comparing experimental setups across laboratories is becoming necessary. Here, we present 1O∗2 measurements from four photosensitizing molecules in four photoreactor setups at three research institutions, including two xenon lamps of different strengths and two multi-bulb UVA + UVB broad-band systems. The production of 1O∗2 was investigated from perinaphthenone, lignin, and juglone, which are photosensitizers with atmospherically relevant light absorbing moieties, as well as from Rose Bengal, a standard photosensitizer. Two chemical actinometers, 2-nitrobenzaldehyde and p-nitroanisole/pyridine, were used to quantify photon fluxes and calculate rates of light absorbance for photosensitizers for each photoreactor. We compared two commonly used 1O∗2 quantification methods, chemical probe method using furfuryl alcohol, as well as direct 1O∗2 phosphorescence detection at 1270 nm. Rates of light absorbance across ex perimental setups for each photosensitizer ranged between 0.2 and 62 × 10−5 molphotons L−1 s−1, while 1O∗2 steady-state concentrations ranged between 0.01 and 129 × 10−11 M. Despite order of magnitude differences in rate of light ab sorbance and 1O∗2 steady state concentrations, normalizingto 1O∗2 quantum yields showed good inter-laboratory agreement but only for the sensitizers with high quantum yields:perinaphthenone (94 % ± 9 %–112 % ± 17 %) and for Rose Bengal (67 % ± 15 %–87 % ± 5 %). 1O∗2 quantum yields for lignin and juglone increased with decreasing irradiation wavelength, highlighting a wavelength-dependence. Finally,we make five recommendations to improve the accuracy and reproducibility of 1O∗2 measurements for the atmospheric chemistry community. These recommendations include considering wavelength-dependent quantum yields, avoiding suppression of 1O∗2, controlling and reporting photoreactor temperature, considering light scattering from nanoparticles,and conducting control experiments. These recommendations can serve as guidelines to build future photoreactors as well as help standardize 1O∗2 measurements in studying photochemical processing of atmospheric aerosols and droplets.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 10,
  "authors": [
    {
      "name": "K. Gemmell"
    },
    {
      "name": "L. Heinlein"
    },
    {
      "name": "E. Petersen-Sonn"
    },
    {
      "name": "C. Sardena"
    },
    {
      "name": "Z. Guo"
    },
    {
      "name": "N. Marino-Ocampo"
    },
    {
      "name": "B. Heyne"
    },
    {
      "name": "C. George"
    },
    {
      "name": "C. Anastasio"
    },
    {
      "name": "N. Borduas-Dedekind"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/aqvyx7vvt3z48.bib",
  "cited_by": 0,
  "doi": "10.5194/amt-19-3961-2026",
  "fulltext_url": null,
  "id": "aqvyx7vvt3z48",
  "issns": [
    "1867-1381",
    "1867-8548"
  ],
  "landing_url": "https://hal.science/hal-05664574v1",
  "language": "en",
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.chim"
    ],
    [
      "hal",
      "0.sde"
    ],
    [
      "hal",
      "1.chim.cata"
    ],
    [
      "hal",
      "1.sde.es"
    ],
    [
      "openalex",
      "1902|Atmospheric chemistry and aerosols"
    ]
  ],
  "openalex": "W7165017499",
  "pdf_url": "https://hal.science/hal-05664574/document",
  "pmcid": null,
  "pmid": null,
  "published": "2026-06-17",
  "publisher": "European Geosciences Union",
  "ris": "https://research.draconitic.com/paper/aqvyx7vvt3z48.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:52Z",
      "native_id": "hal-05664574",
      "source": "hal",
      "url": "https://hal.science/hal-05664574v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "hal:1.chim.cata",
      "subfield": "catalysis"
    },
    {
      "field": "earth",
      "origin": "hal:0.sde",
      "subfield": "environmental-science"
    }
  ],
  "title": "Measuring molecular singlet oxygen (1O2*) from atmospheric photosensitizers: Intercomparison of techniques, irradiation setups, data analysis and protocol recommendations",
  "title_text": "Measuring molecular singlet oxygen (1O2*) from atmospheric photosensitizers: Intercomparison of techniques, irradiation setups, data analysis and protocol recommendations",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:52Z",
  "url": "https://research.draconitic.com/paper/aqvyx7vvt3z48",
  "venue": "Atmospheric Measurement Techniques",
  "versions": []
}