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DOE OSTI · 3029886

Redox‐Dependent Luminescence in a Pentavalent Uranyl Complex

Valerio, Leyla R. [Univ. of Rochester, NY (United States)]·Sen, Asmita [State Univ. of New York (SUNY), Buffalo, NY (United States)]·Brennessel, William W. [Univ. of Rochester, NY (United States)]·Milsmann, Carsten [Univ. of Delaware, Newark, DE (United States)] (ORCID:0000000292495199)·Autschbach, Jochen [State Univ. of New York (SUNY), Buffalo, NY (United States)] (ORCID:000000019392877X)·Matson, Ellen M. [Univ. of Rochester, NY (United States)] (ORCID:0000000337538288)
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Abstract

The chemistry of pentavalent uranyl is of high interest due to the ion's central role as an intermediate in nuclear separations. However, due to the instability of [UO 2 ] + , little is known about its electronic structure. The synthesis and characterization of a pentavalent uranyl complex supported by a pyridine dipyrrolide pincer‐type ligand are reported. The pentavalent species is isolated following reduction of the hexavalent uranyl congener, allowing for direct comparisons to be made between the two species. The [UO 2 ] 2+ analog is nonemissive, but upon reduction, luminescence is “switched on” in the pentavalent uranyl complex, affording emission from a high‐energy state. Quantum chemical calculations support the experimental findings and help provide insight into the electronic structure of the excited states of the reduced complex. This work provides a unique example of ligand‐based non‐Kasha emission from a molecular pentavalent uranyl complex.

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Valerio, Leyla R. [Univ. of Rochester, NY (United States)], Sen, Asmita [State Univ. of New York (SUNY), Buffalo, NY (United States)], Brennessel, William W. [Univ. of Rochester, NY (United States)], Milsmann, Carsten [Univ. of Delaware, Newark, DE (United States)] (ORCID:0000000292495199), Autschbach, Jochen [State Univ. of New York (SUNY), Buffalo, NY (United States)] (ORCID:000000019392877X), Matson, Ellen M. [Univ. of Rochester, NY (United States)] (ORCID:0000000337538288). 2025-12-09. Redox‐Dependent Luminescence in a Pentavalent Uranyl Complex. https://doi.org/10.1002/ceur.202500269

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