skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Theoretical spectroscopy study of the low-lying electronic states of UX and UX +, X = F and Cl

Abstract

Spectroscopic constants (T e, r e, B 0, ω e, ω ex e) have been calculated for the low-lying electronic states of UF, UF +, UCl, and UCl + using complete active space 2nd-order perturbation theory (CASPT2), with a series of correlation consistent basis sets. The latter included those based on both pseudopotential (PP) and all-electron Douglas-Kroll-Hess (DK) Hamiltonians for the U atom. Spin orbit effects were included a posteri using the state interacting method using both PP and Breit Pauli (BP) operators, as well as from exact two-component (X2C) methods for U + and UF +. Complete basis set (CBS) limits were obtained by extrapolation where possible and the PP and BP calculations were compared at their respective CBS limits. The PP-based method was shown to be reliable in calculating spectroscopic constants, in particular when using the state interacting method with CASPT2 energies (SO-CASPT2). The two component calculations were limited by computational resources and could not include electron correlation from the nominally closed shell 6s and 6p orbitals of U. UF and UCl were both calculated to have Ω=9/2 ground states. The first excited state of UCl was calculated to be an Ω=7/2 state at 78 cm -1 asmore » opposed to the same state at 435 cm-1 in UF, and the other low-lying states of UCl showed a similar compression relative to UF. Likewise UF+ and UCl+ both have Ω=4 ground states and the manifold of low-lying excited Ω = 3, 2, 1, 0 states were energetically closer together in UCl + than in UF +, ranging up to 776 cm -1 in UF + and only 438 cm -1 in UCl +. As in previous research, the final PP-based SO-CASPT2 results for UF + and UF agree well with experiment, and are expected to be predictive for UCl and UCl +, which are reported here for the first time.« less

Authors:
 [1]; ORCiD logo [1]
  1. Washington State Univ., Pullman, WA (United States)
Publication Date:
Research Org.:
Washington State Univ., Pullman, WA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1224465
Alternate Identifier(s):
OSTI ID: 1225988
Grant/Contract Number:  
SC0008501; FG02-12ER16329
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 143; Journal Issue: 18; Journal ID: ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; UF; UCl; uranium halides; uranium halide cations; ab initio; ground states; excitation energies; spin orbit interactions; electron correlation calculations; electron spectroscopy

Citation Formats

Bross, David H., and Peterson, Kirk A. Theoretical spectroscopy study of the low-lying electronic states of UX and UX+, X = F and Cl. United States: N. p., 2015. Web. doi:10.1063/1.4935492.
Bross, David H., & Peterson, Kirk A. Theoretical spectroscopy study of the low-lying electronic states of UX and UX+, X = F and Cl. United States. https://doi.org/10.1063/1.4935492
Bross, David H., and Peterson, Kirk A. Fri . "Theoretical spectroscopy study of the low-lying electronic states of UX and UX+, X = F and Cl". United States. https://doi.org/10.1063/1.4935492. https://www.osti.gov/servlets/purl/1224465.
@article{osti_1224465,
title = {Theoretical spectroscopy study of the low-lying electronic states of UX and UX+, X = F and Cl},
author = {Bross, David H. and Peterson, Kirk A.},
abstractNote = {Spectroscopic constants (Te, re, B0, ωe, ωexe) have been calculated for the low-lying electronic states of UF, UF+, UCl, and UCl+ using complete active space 2nd-order perturbation theory (CASPT2), with a series of correlation consistent basis sets. The latter included those based on both pseudopotential (PP) and all-electron Douglas-Kroll-Hess (DK) Hamiltonians for the U atom. Spin orbit effects were included a posteri using the state interacting method using both PP and Breit Pauli (BP) operators, as well as from exact two-component (X2C) methods for U+ and UF+. Complete basis set (CBS) limits were obtained by extrapolation where possible and the PP and BP calculations were compared at their respective CBS limits. The PP-based method was shown to be reliable in calculating spectroscopic constants, in particular when using the state interacting method with CASPT2 energies (SO-CASPT2). The two component calculations were limited by computational resources and could not include electron correlation from the nominally closed shell 6s and 6p orbitals of U. UF and UCl were both calculated to have Ω=9/2 ground states. The first excited state of UCl was calculated to be an Ω=7/2 state at 78 cm-1 as opposed to the same state at 435 cm-1 in UF, and the other low-lying states of UCl showed a similar compression relative to UF. Likewise UF+ and UCl+ both have Ω=4 ground states and the manifold of low-lying excited Ω = 3, 2, 1, 0 states were energetically closer together in UCl+ than in UF+, ranging up to 776 cm-1 in UF+ and only 438 cm-1 in UCl+. As in previous research, the final PP-based SO-CASPT2 results for UF+ and UF agree well with experiment, and are expected to be predictive for UCl and UCl+, which are reported here for the first time.},
doi = {10.1063/1.4935492},
url = {https://www.osti.gov/biblio/1224465}, journal = {Journal of Chemical Physics},
issn = {0021-9606},
number = 18,
volume = 143,
place = {United States},
year = {2015},
month = {11}
}

Works referenced in this record:

Handbook of Basic Atomic Spectroscopic Data
journal, December 2005


An efficient second-order MC SCF method for long configuration expansions
journal, April 1985


Spectroscopy and Structure of the Simplest Actinide Bonds
journal, October 2014


On the effectiveness of CCSD(T) complete basis set extrapolations for atomization energies
journal, July 2011


Probing the electronic structure of UO+ with high-resolution photoelectron spectroscopy
journal, October 2006


Relativistic Hamiltonians for Chemistry: A Primer
journal, November 2011


Multireference perturbation theory for large restricted and selected active space reference wave functions
journal, April 2000


How accurate are electronic structure methods for actinoid chemistry?
journal, March 2011


New spectroscopic data on high-lying excited levels of atomic uranium
journal, January 1982


Ab initio total atomization energies of small molecules — towards the basis set limit
journal, September 1996


Stark and Zeeman effect in the [18.6]3.5 – X(1)4.5 transition of uranium monofluoride, UF
journal, June 2014


Composite thermochemistry of gas phase U(VI)-containing molecules
journal, December 2014


Benchmarking Electronic Structure Calculations on the Bare UO 2 2+ Ion: How Different are Single and Multireference Electron Correlation Methods?
journal, November 2009


Correlation consistent basis sets for actinides. I. The Th and U atoms
journal, February 2015


Diatomic Molecule Electronic Structure beyond Simple Molecular Constants
journal, September 1982


Electronic Spectroscopy of UO
journal, September 1997


Quantum Chemical Calculations and Experimental Investigations of Molecular Actinide Oxides
journal, January 2015


All-Electron Scalar Relativistic Basis Sets for the Actinides
journal, February 2011


Theoretical study on ThF + , a prospective system in search of time-reversal violation
journal, April 2015


An infinite-order two-component relativistic Hamiltonian by a simple one-step transformation
journal, February 2007


An efficient internally contracted multiconfiguration–reference configuration interaction method
journal, November 1988


All-electron Douglas–Kroll–Hess and pseudopotential study on the low-lying states of uranium hydride UH
journal, January 2008


A modified definition of the zeroth-order Hamiltonian in multiconfigurational perturbation theory (CASPT2)
journal, September 2004


Gaussian basis sets for use in correlated molecular calculations. III. The atoms aluminum through argon
journal, January 1993


Internally contracted multiconfiguration-reference configuration interaction calculations for excited states
journal, October 1992


Relativistic Pseudopotentials: Their Development and Scope of Applications
journal, September 2011


All-Electron Hybrid Density Functional Calculations on UF n and UCl n ( n = 1−6)
journal, May 2005


Parallel Douglas–Kroll energy and gradients in NWChem: Estimating scalar relativistic effects using Douglas–Kroll contracted basis sets
journal, January 2001


Spin-orbit matrix elements for internally contracted multireference configuration interaction wavefunctions
journal, November 2000


A second order multiconfiguration SCF procedure with optimum convergence
journal, June 1985


Gaussian basis sets for use in correlated molecular calculations. X. The atoms aluminum through argon revisited
journal, June 2001


The Energy Levels of a Rotating Vibrator
journal, September 1932


A Fock space coupled cluster study on the electronic structure of the UO2, UO2+, U4+, and U5+ species
journal, September 2007


Electronic structure of UH, UF, and their ions
journal, July 1983


Spectroscopic and Theoretical Investigations of UF and UF +
journal, February 2013


An ab initio study of excited states of U and UF
journal, March 2003


Reactions of Laser-Ablated U Atoms with HF: Infrared Spectra and Quantum Chemical Calculations of HUF, UH, and UF in Noble Gas Solids
journal, August 2014


Actinide speciation in the environment
journal, January 2003


An efficient method for the evaluation of coupling coefficients in configuration interaction calculations
journal, April 1988


Third-order multireference perturbation theory The CASPT3 method
journal, October 1996


Actinide speciation in the environment
journal, June 2007


Internally contracted multiconfiguration-reference configuration interaction calculations for excited states
journal, October 1992


Third-order multireference perturbation theory The CASPT3 method
journal, October 1996


The Energy Levels of a Rotating Vibrator
journal, September 1932


New spectroscopic data on high-lying excited levels of atomic uranium
journal, January 1982


    Works referencing / citing this record:

    Correlation consistent basis sets for lanthanides: The atoms La–Lu
    journal, August 2016


    Spectroscopic and theoretical studies of ThCl and ThCl +
    journal, February 2017