Visible and near-infrared excitation spectra from the neptunyl ion doped into a uranyl tetrachloride lattice

Barker, Beau J.; Berg, John M.; Kozimor, Stosh A.; Wozniak, Nicholas R.; Wilkerson, Marianne Perry

doi:10.1016/j.molstruc.2015.12.027

Title: Visible and near-infrared excitation spectra from the neptunyl ion doped into a uranyl tetrachloride lattice

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Abstract

We present that visible and near-infrared illumination induces 5f-5f and ligand-to-metal charge-transfer (LMCT) transitions of the neptunyl tetrachloride anion in polycrystalline Cs₂U(Np)O₂Cl₄, and results in near-infrared luminescence from the second electronically excited state to the ground state. This photoluminescence is used as a detection method to collect excitation spectra throughout the near-infrared and visible regions. The excitation spectra of LMCT transitions in excitation spectra were identified in previous work. Here the measurement and analysis is extended to include both LMCT and intra-5f transitions. The results manifest variation in structural properties of the neptunium-oxo bond among the low-lying electronic states. Vibronic intensity patterns and energy spacings are used to compare bond lengths and vibrational frequencies in the excited states, confirming significant characteristic differences between those excited by 5f-5f transitions from those due to LMCT transitions. Lastly, results are compared with recently published RASPT2/SO calculations of [NpO₂Cl₄]^2-.

Authors:

Barker, Beau J. ^[1];

^[1]; Kozimor, Stosh A. ^[1]; Wozniak, Nicholas R. ^[1];

^[1]

Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Publication Date:: Tue Dec 15 00:00:00 EST 2015

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1457255

Alternate Identifier(s):: OSTI ID: 1396701

Report Number(s):: LA-UR-15-26413
Journal ID: ISSN 0022-2860

Grant/Contract Number:: AC52-06NA25396

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Molecular Structure

Additional Journal Information:: Journal Volume: 1108; Journal Issue: C; Journal ID: ISSN 0022-2860

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Actinide; Electronic structure; Excitation spectrum; Intra-5f; Ligand-to-metal charge-transfer; Neptunyl

Citation Formats


                    Barker, Beau J., Berg, John M., Kozimor, Stosh A., Wozniak, Nicholas R., and Wilkerson, Marianne Perry. Visible and near-infrared excitation spectra from the neptunyl ion doped into a uranyl tetrachloride lattice.  United States: N. p., 2015. 
Web.  doi:10.1016/j.molstruc.2015.12.027.

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                    Barker, Beau J., Berg, John M., Kozimor, Stosh A., Wozniak, Nicholas R., & Wilkerson, Marianne Perry. Visible and near-infrared excitation spectra from the neptunyl ion doped into a uranyl tetrachloride lattice.  United States.  https://doi.org/10.1016/j.molstruc.2015.12.027

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                    Barker, Beau J., Berg, John M., Kozimor, Stosh A., Wozniak, Nicholas R., and Wilkerson, Marianne Perry. Tue .  
"Visible and near-infrared excitation spectra from the neptunyl ion doped into a uranyl tetrachloride lattice".  United States.  https://doi.org/10.1016/j.molstruc.2015.12.027.  https://www.osti.gov/servlets/purl/1457255.

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@article{osti_1457255,

  title        = {Visible and near-infrared excitation spectra from the neptunyl ion doped into a uranyl tetrachloride lattice},

  author       = {Barker, Beau J. and Berg, John M. and Kozimor, Stosh A. and Wozniak, Nicholas R. and Wilkerson, Marianne Perry},

  abstractNote = {We present that visible and near-infrared illumination induces 5f-5f and ligand-to-metal charge-transfer (LMCT) transitions of the neptunyl tetrachloride anion in polycrystalline Cs2U(Np)O2Cl4, and results in near-infrared luminescence from the second electronically excited state to the ground state. This photoluminescence is used as a detection method to collect excitation spectra throughout the near-infrared and visible regions. The excitation spectra of LMCT transitions in excitation spectra were identified in previous work. Here the measurement and analysis is extended to include both LMCT and intra-5f transitions. The results manifest variation in structural properties of the neptunium-oxo bond among the low-lying electronic states. Vibronic intensity patterns and energy spacings are used to compare bond lengths and vibrational frequencies in the excited states, confirming significant characteristic differences between those excited by 5f-5f transitions from those due to LMCT transitions. Lastly, results are compared with recently published RASPT2/SO calculations of [NpO2Cl4]2-.},

  doi          = {10.1016/j.molstruc.2015.12.027},

  journal      = {Journal of Molecular Structure},

  number       = C,

  volume       = 1108,

  place        = {United States},

  year         = {Tue Dec 15 00:00:00 EST 2015},

  month        = {Tue Dec 15 00:00:00 EST 2015}

}

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