Route to Chemical Accuracy for Computational Uranium Thermochemistry

Zhang, Chaoqun; Cheng, Lan

doi:10.1021/acs.jctc.2c00812

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Route to Chemical Accuracy for Computational Uranium Thermochemistry

Zhang, Chaoqun·Cheng, Lan

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Abstract

Benchmark spinor-based relativistic coupled-cluster calculations for the ionization energies of the uranium atom, the uranium monoxide molecule (UO), and the uranium dioxide molecule (UO 2 ) and for the bond dissociation energies of UO and UO 2 are reported. The accuracy of these calculations in the treatments of relativistic, electron correlation, and basis-set effects is analyzed. Furthermore, the intrinsic convergence of the computed results and the favorable comparison with the experimental values demonstrate the unique applicability of the spinor representation of quantum-chemical methods to open-shell uranium-containing atomic and molecular species with uranium oxidation states ranging from U(0) to U(V).

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Zhang, Chaoqun, Cheng, Lan. 2022-10-07. Route to Chemical Accuracy for Computational Uranium Thermochemistry. https://doi.org/10.1021/acs.jctc.2c00812

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