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Updated: Jun 16, 2026

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Fluorescence of the perylene radical cation and an inaccessible D(0)/D(1) conical intersection: An MMVB, RASSCF, and
Andrei M Tokmachev1, Martial Boggio-Pasqua, David Mendive-Tapia
1Department of Chemistry, Imperial College London, London SW7 2AZ, United Kingdom.
Abstract:
The photophysics of the perylene radical cation (Pe(+)) was studied using the molecular mechanics-valence bond (MMVB) hybrid force field. Potential energy surfaces of the first three electronic states were investigated. Geometry optimizations of critical points-including conical intersections between the relevant electronic states-were performed using the MMVB analytical energy gradient for cations. No accessible planar conical intersection between the D(0) and D(1) states of Pe(+) was found; this is consistent with the experimentally observed D(1) lifetimes and the observation of D(1) emission from this cation in the condensed phase. Benchmark RASSCF and TD-DFT calculations support the reliability of the MMVB results.
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