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Updated: Jun 9, 2026
11:44
Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
Electronic structure and spectroscopy of ClSO.
Tarek Trabelsi1, Joseph S Francisco2
1Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6243, USA.
The Journal of Chemical Physics
|June 8, 2026
Summary
High-accuracy theoretical calculations characterize the ClSO+ cation, revealing its strongly bound ground state and predicting ionization energies. These findings offer a molecular framework for interpreting experimental spectra of ClSO.
Area of Science:
- Chemical Physics
- Computational Chemistry
- Spectroscopy
Background:
- Synchrotron photoionization mass spectrometry identified ClSO+ in Cl2SO photochemistry.
- Vibronically structured near-threshold ionization of the ClSO radical was observed.
Purpose of the Study:
- Provide a high-accuracy theoretical characterization of the ClSO+ cation.
- Offer a molecular framework for interpreting experimental data of ClSO.
Main Methods:
- Coupled-cluster calculations (all-electron scalar-relativistic, explicitly correlated) for structures and ionization energies.
- MRCI+Q and EOM-CCSD methods for low-lying singlet states of ClSO+.
- Calculation of rotational constants, IR intensities, and electronic excitations.
Main Results:
- Benchmark adiabatic (9.47 eV) and vertical (9.67 eV) ionization energies for ClSO.
- Strongly bound ClSO+ ground-state potential with a Cl-S bond dissociation energy of 3.21 eV.
- Predicted dominant near-UV electronic transition and low-lying dark states.
Conclusions:
- Theoretical data provide a molecular framework for interpreting ClSO threshold ionization spectra.
- Results aid in assigning or anticipating ClSO+ features in VUV/UV experiments.
- Detailed characterization of ClSO+ properties including structure, bonding, and electronic excitations.
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