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DOE OSTI · 1656946

Mapping the Electronic Structure of the Uranium(VI) Dinitride Molecule, UN 2

Liu, Gaoxiang·Zhang, Chaoqun·Ciborowski, Sandra M.·Asthana, Ayush·Cheng, Lan·Bowen, Kit H.
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Abstract

A combined anion photoelectron spectroscopic and relativistic electronic-structure computational study of the electronic structure of the UN 2 molecule is reported. Since the photoelectron spectrum of uranium dinitride’s negative ion, UN 2 - , (UN 2 plus an additional electron) directly reflects the electronic structure of neutral UN 2 , we have measured and relied upon the photoelectron spectrum of the UN 2 – anion as a means of mapping the electronic structure of neutral UN 2 . In addition to the electron affinity of the UN 2 ground state (the energy released when attaching an electron to UN 2 molecule), energy levels of the UN 2 excited states (electronic states with higher energies than the ground state) were well characterized by the close interplay between experiment and high-level theory. We found that both electron attachment and electronic excitation significantly bend the UN 2 molecule and elongate its U≡N bond. Implications for the activation of UN 2 are discussed.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYactinide chemistrycoupled cluster theoryrelativistic effectsrelativistic quantum chemistryuranium chemistry

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Liu, Gaoxiang, Zhang, Chaoqun, Ciborowski, Sandra M., Asthana, Ayush, Cheng, Lan, Bowen, Kit H.. 2020-07-23. Mapping the Electronic Structure of the Uranium(VI) Dinitride Molecule, UN 2. https://doi.org/10.1021/acs.jpca.0c03735

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