Pentacene (C22H14, PEN) and perfluoropentacene (C22F14, PFP) are considered promising building blocks of organic semiconductors. Using gas-phase anion photoelectron spectroscopy, the adiabatic electron affinity of PEN and PFP molecules is determined to be 1.43 ± 0.03 and 2.74 ± 0.03 eV, respectively, and the S0-T1 transition energies of PEN and PFP are evaluated to be 0.96 ± 0.06 and 0.72 ± 0.05 eV, respectively. Photoelectron spectra indicate that the vibronic coupling in PFP is stronger than that in PEN. Quantum chemistry calculations demonstrate that the strong vibronic coupling originates from significant structural displacement upon electron injection to PFP.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry