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Updated: Jul 19, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Vibronic coupling in the ground and excited states of oligoacene cations
Roel S Sanchez-Carrera1, Veaceslav Coropceanu, Demetrio A da Silva Filho
1School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA.
Abstract:
The vibrational coupling in the ground and excited states of positively charged naphthalene, anthracene, tetracene, and pentacene molecules is studied on the basis of a joint experimental and theoretical study of ionization spectra using high-resolution gas-phase photoelectron spectroscopy and first-principles correlated quantum-mechanical calculations. Our theoretical and experimental results reveal that, while the main contribution to relaxation energy in the ground state of oligoacene systems comes from high-energy vibrations, the excited-state relaxation energies show a significant redistribution toward lower-frequency vibrations. A direct correlation is found between the nature of the vibronic interaction and the pattern of the electronic state structure.
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