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DOE OSTI · 2377132

Systematic Study of Solid-State U(VI) Photoreactivity: Long-Lived Radicalization and Electron Transfer in Uranyl Tetrachloride

Herder, Jordan A.·Kruse, Samantha J.·Nicholas, Aaron D.·Forbes, Tori Z.·Walter, Eric D.·Cho, Herman·Cahill, Christopher L.
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Abstract

Reported are the syntheses, structural characterizations and luminescence properties of three novel [UO 2 Cl 4 ] 2- bearing compounds containing substituted 1,1’-dialkyl-4,4’-bipyridinum dications (i.e. viologens). These compounds undergo photoinduced luminescence quenching upon exposure to UV radiation. Further, this reactivity is concurrent with two phenomena: radicalization of the uranyl tetrachloride anion and photoelectron transfer to the viologen which constitutes the formal transfer of one electron from the [UO 2 Cl 4 ] 2- to the viologen species. This behavior is elucidated using electron paramagnetic resonance (EPR) spectroscopy and further probed through a series of characterization and computational techniques including Rehm-Weller analysis, time-dependent density functional theory (TD-DFT), and density of states (DOS). This work provides a systematic study of the photoreactivity of the uranyl unit in the solid state, an under-described aspect of fundamental uranyl chemistry.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYActinide chemistryAnionsCationsIrradiationMaterialsPyridines

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Herder, Jordan A., Kruse, Samantha J., Nicholas, Aaron D., Forbes, Tori Z., Walter, Eric D., Cho, Herman, Cahill, Christopher L.. 2024-03-04. Systematic Study of Solid-State U(VI) Photoreactivity: Long-Lived Radicalization and Electron Transfer in Uranyl Tetrachloride. https://doi.org/10.1021/acs.inorgchem.3c04144

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