Caption:
(a) Molar absorption coefficients for ferric and ferrous oxalate complexes along with selected experimentally determined quantum yields. Unless otherwise specified, the quantum yields refer to the $\mathrm{\left[Fe^{3+}(C_2O_4)_3\right]^{3-}}$ complex or the complex distribution is not considered. The standard deviation reported by Demas et al. [94] is smaller than the used marker size. The continuous fit provided by Straub et al. [378] is based on experimental data from refs. [148, 169, 300]. (b) Relative intensities, as specified by the manufacturer, for the combined Deuterium/Halogen lamp (Ocean Optics, DH-2000-S-DUV) used for continuous broadband light irradiation and the pulsed LED (ILA5150 LPSv3) used for particle illumination.

Notes:
Data can be obtained from the specified references.

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Determination of the quantum yield of the ferrioxalate actinometer with electrically
calibrated radiometers. The Journal of Physical Chemistry, 85(19):2766–2771.
DOI: https://doi.org/10.1021/j150619a015.

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polycarboxylate complexes: roles in the chemistry of atmospheric and surface
waters. Environmental Science & Technology, 27(12):2517–2522. DOI: https:
//doi.org/10.1021/es00048a032.

[148] Goldstein, S. & Rabani, J. (2008). The ferrioxalate and iodide–iodate actinometers in the uv region. Journal of Photochemistry and Photobiology A: Chemistry, 193(1):50–55. DOI: https://doi.org/10.1016/j.jphotochem.2007.06.006.

[169] Hatchard, C. G., Parker, C. A., & Bowen, E. J. (1956). A new sensitive chemical
actinometer - ii. potassium ferrioxalate as a standard chemical actinometer.
Proceedings of the Royal Society of London. Series A. Mathematical and
Physical Sciences, 235(1203):518–536. DOI: https://doi.org/10.1098/rspa.1956.
0102.

[226] Lee, J. & Seliger, H. H. (1964). Quantum yield of the ferrioxalate actinometer.
The Journal of Chemical Physics, 40(2):519–523. DOI: https://doi.org/10.
1063/1.1725147.

[300] Parker, C. A. & Hatchard, C. G. (1959). Photodecomposition of complex
oxalates—some preliminary experiments by flash photolysis. The Journal of
Physical Chemistry, 63(1):22–26. DOI: https://doi.org/10.1021/j150571a009.

[313] Pozdnyakov, I. P., Kel, O. V., Plyusnin, V. F., Grivin, V. P., & Bazhin,
N. M. (2008). New insight into photochemistry of ferrioxalate. The Journal
of Physical Chemistry A, 112(36):8316–8322. PMID: 18707071. DOI: https:
//doi.org/10.1021/jp8040583.

[378] Straub, S., Brünker, P., Lindner, J., & Vöhringer, P. (2018). Femtosecond
infrared spectroscopy reveals the primary events of the ferrioxalate actinometer.
Phys. Chem. Chem. Phys., 20:21390–21403. DOI: https://doi.org/10.1039/
C8CP03824D.

[420] Weller, C., Horn, S., & Herrmann, H. (2013). Effects of fe(iii)-concentration,
speciation, excitation-wavelength and light intensity on the quantum yield of
iron(iii)-oxalato complex photolysis. Journal of Photochemistry and Photobiology A: Chemistry, 255:41–49. DOI: https://doi.org/10.1016/j.jphotochem.
2013.01.014.