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This review summarizes the recent developments regarding the use of uranium as nuclear fuel, including recycling and health aspects, elucidated from a chemical point of view, i.e., emphasizing the rich uranium coordination chemistry, which has also raised interest in using uranium compounds in synthesis and catalysis. A number of novel uranium coordination features are addressed, such the emerging number of U(II) complexes and uranium nitride complexes as a promising class of materials for more efficient and safer nuclear fuels. The current discussion about uranium triple bonds is addressed by quantum chemical investigations using local vibrational mode force constants as quantitative bond strength descriptors based on vibrational spectroscopy. The local mode analysis of selected uranium nitrides, N≡U≡N, U≡N, N≡U=NH and N≡U=O, could confirm and quantify, for the first time, that these molecules exhibit a UN triple bond as hypothesized in the literature. We hope that this review will inspire the community interested in uranium chemistry and will serve as an incubator for fruitful collaborations between theory and experimentation in exploring the wealth of uranium chemistry.
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This content will become publicly available on May 30, 2025
Chemical bonding in Uranium‐based materials: A local vibrational mode case study of Cs 2UO 2Cl 4 and UCl 4 crystals
Abstract The Local Vibrational Mode Analysis, initially applied to diverse molecular systems, was extended to periodic systems in 2019. This work introduces an enhanced version of the LModeA software, specifically designed for the comprehensive analysis of two and three‐dimensional periodic structures. Notably, a novel interface with theCrystalpackage was established, enabling a seamless transition from molecules to periodic systems using a unified methodology. Two distinct sets of uranium‐based systems were investigated: (i) the evolution of the Uranyl ion (UO) traced from its molecular configurations to the solid state, exemplified by CsUOCl and (ii) Uranium tetrachloride (UCl) in both its molecular and crystalline forms. The primary focus was on exploring the impact of crystal packing on key properties, including IR and Raman spectra, structural parameters, and an in‐depth assessment of bond strength utilizing local mode perspectives. This work not only demonstrates the adaptability and versatility of LModeA for periodic systems but also highlights its potential for gaining insights into complex materials and aiding in the design of new materials through fine‐tuning.
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- Award ID(s):
- 2102461
- PAR ID:
- 10526198
- Publisher / Repository:
- Journal of Computational Chemistry
- Date Published:
- Journal Name:
- Journal of Computational Chemistry
- Volume:
- 45
- Issue:
- 14
- ISSN:
- 0192-8651
- Page Range / eLocation ID:
- 1130 to 1142
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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