Interrogating the Intramolecular Charge-Transfer State of a Julolidine-Anthracene Donor-Acceptor Molecule with Femtosecond Stimulated Raman Spectroscopy

The nature of the lowest-energy charge-transfer (CT)excited state of the donor acceptor molecule, 3,5-dimethyl-4-(9-anthracenyl)julolidine (DMJ- An) is investigated using femtosecond stimulated Raman spectroscopy. Transient Raman spectra are presented with subpicosecond time resolution, and peaks are assigned based on the published Raman modes of the reference molecule phenyl anthracene. The results indicate that the CT excited state is dominated by a fully charge separated radical ion pair state with minimal contribution from the local anthracene pi-pi* state.