Title: Spectroscopic and theoretical studies of ThCl and ThCl⁺

Abstract

In this paper, the electronic structures of ThCl and ThCl⁺ have been examined using laser induced fluorescence and two-photon ionization techniques. Rotationally resolved spectra, combined with the predictions from relativistic electronic structure calculations, show that the ground state of the neutral molecule is Th⁺(7s²6d)Cl^-, ${\text{X}}^2{\mathrm{\Delta }}_{3/2}$. Dispersed fluorescence spectra for ThCl revealed the ground state vibrational levels v = 0-10 and low energy electronic states that also originate from the atomic ion 7s²6d configuration. Pulsed field ionization—zero kinetic energy photoelectron spectroscopy established an ionization energy (IE) for ThCl of 51 344(5) cm^-1, and the ThCl⁺ vibrational term energies of the v = 1-3 levels. The zero-point level of the first electronically excited state was found at 949(2) cm^-1. Comparisons with high-level theoretical results indicate that the ground and excited states are Th²⁺(7s6d)Cl^- ${\text{X}}^3{\mathrm{\Delta }}_1$ and Th²⁺(7s²)Cl^- ${}_1\mathrm{\Sigma }_{+}$, respectively. Finally, relativistic coupled cluster composite thermochemistry calculations yielded an IE within 1.2 kcal/mol of experiment and a bond dissociation energy (118.3 kcal/mol) in perfect agreement with previous experiments.

Authors:

VanGundy, Robert A. ^[1]; Bartlett, Joshua H. ^[1]; Heaven, Michael C. ^[1]; Battey, Samuel R. ^[2]; Peterson, Kirk A.  ^[2]

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+ Show Author Affiliations

1. Emory Univ., Atlanta, GA (United States). Dept. of Chemistry
2. Washington State Univ., Pullman, WA (United States). Dept. of Chemistry

Publication Date:

2017-02-07

Research Org.:

Emory Univ., Atlanta, GA (United States); Washington State Univ., Pullman, WA (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1465687

Alternate Identifier(s):

OSTI ID: 1361762

Grant/Contract Number:  

FG02-01ER15153; FG02-12ER16329

Resource Type:

Accepted Manuscript

Journal Name:

Journal of Chemical Physics

Additional Journal Information:

Journal Volume: 146; Journal Issue: 5; 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; ionization; excited states; basis sets; laser induced fluorescence; electron spectroscopy; ligand fields; ground states; display devices; dissociation energies; fluorescence spectra