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Updated: Aug 20, 2026
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Theoretical fine spectroscopy with symmetry adapted cluster-configuration interaction general-R method: first-row
Kei Kuramoto1, Masahiro Ehara, Hiroshi Nakatsuji
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto-Daigaku-Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Abstract:
Molecular core ionization spectra and their satellites were studied by the symmetry adapted cluster-configuration interaction (SAC-CI) general-R method. The core-electron binding energies of C, N, O, and F atoms of 22 molecules were calculated with an average deviation of 0.11 eV from the experimental values. The energy splittings between K-shell gerade and ungerade states were calculated and discussed in relation to the bond length. The satellite spectra of the C 1s and N 1s core ionizations of methane and ammonia were investigated. The SAC-CI general-R method gave many shake-up states with moderate intensities, reproducing the general feature of the experimental spectra, and thus enabling the detailed understanding and assignments of the core-electron ionization spectra.
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