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Updated: Aug 3, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
One color resonant two photon ionization spectroscopy of p-methylstyrene and theoretical calculation
Jiangou Huang1, Daoqing Xiao, Weibin Bi
1The State Key Laboratory of Molecular Reaction Dynamics, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
Abstract:
The band origin of the S1<--S0 transition of p-methylstyrene is determined to be 34,276 cm-1 by one color resonant two photon ionization (1C-R2PI) method, which is red shifted by 3811 cm-1 with respect to that of benzene. This indicates that the interaction of the methyl and vinyl groups with the ring in the S1 state is greater than that in the S0 state. The active vibrations assigned from the R2PI spectrum are found to be the in-plane ring modes. The bands at 399, 613, 724, and 786 cm-1 are assigned to the vibrations 9b, 6b, 12, and 1, respectively, and discussed in detail. The experimental results are well supported by ab initio and density functional theory (DFT) calculations.
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