TY - JOUR
T1 - Theoretical study of generalized oscillator strengths for the low-lying electronic excitations of CH3Cl and CF3Cl
AU - Watanabe, Noboru
AU - Takahashi, Masahiko
N1 - Funding Information:
This research was supported by the JSPS KAKENHI Grant Nos. 18H01932, 19K21862, and 21H01874. It was also supported in part by the Management Expenses Grants for National Universities Corporation and the Cooperative Research Program of ‘NJRC Mater. & Dev.’.
Publisher Copyright:
© 2022 IOP Publishing Ltd.
PY - 2022/1/5
Y1 - 2022/1/5
N2 - We report a theoretical study of electronic excitation in CH3Cl and CF3Cl by electron impact. Momentum-transfer-dependent generalized oscillator strengths (GOSs) are calculated for transitions to low-lying excited singlet-states at the equation-of-motion coupled-cluster singles and doubles level. The influence of molecular vibration is taken into account in the calculation. The theoretical results show reasonable overall agreement with experimental data reported in the literature. The shapes of the GOS profiles reveal that the 1 1E state of CH3Cl has a valence-Rydberg mixed nature, while that of CF3Cl is of a predominant C-Cl antibonding character. A comparison with the experimental GOSs of CH3Cl provides unambiguous evidence that the 3pe state is lower in energy than the 3pa1 state. Optical oscillator strengths are also calculated and comparison is made with available experimental and other theoretical results.
AB - We report a theoretical study of electronic excitation in CH3Cl and CF3Cl by electron impact. Momentum-transfer-dependent generalized oscillator strengths (GOSs) are calculated for transitions to low-lying excited singlet-states at the equation-of-motion coupled-cluster singles and doubles level. The influence of molecular vibration is taken into account in the calculation. The theoretical results show reasonable overall agreement with experimental data reported in the literature. The shapes of the GOS profiles reveal that the 1 1E state of CH3Cl has a valence-Rydberg mixed nature, while that of CF3Cl is of a predominant C-Cl antibonding character. A comparison with the experimental GOSs of CH3Cl provides unambiguous evidence that the 3pe state is lower in energy than the 3pa1 state. Optical oscillator strengths are also calculated and comparison is made with available experimental and other theoretical results.
KW - EOM-CCSD
KW - electron energy loss spectroscopy
KW - generalized oscillator strength
KW - optical oscillator strength
KW - vibronic effect
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U2 - 10.1088/1361-6455/ac4a22
DO - 10.1088/1361-6455/ac4a22
M3 - Article
AN - SCOPUS:85125738366
SN - 0953-4075
VL - 55
JO - Journal of Physics B: Atomic, Molecular and Optical Physics
JF - Journal of Physics B: Atomic, Molecular and Optical Physics
IS - 1
M1 - 015201
ER -