1 research outputs found
Outsourcing Intersystem Crossing without Heavy Atoms: Energy Transfer Dynamics in PyridoneBODIPY–C<sub>60</sub> Complexes
The
excited state dynamics in two fully characterized pyridoneBODIPY–fullerene
complexes were investigated using time-resolved spectroscopy. Photoexcitation
was initially localized on the pyridoneBODIPY chromophore. The energy
was rapidly transferred to the fullerene, which subsequently underwent
ISC to form a triplet state and returned the energy to the pyridoneBODIPY
via triplet–triplet energy transfer. This ping-pong energy
transfer mechanism resulted in efficient (>85%) overall conversion
of the excited state pyridoneBODIPY constituent despite a complete
lack of ISC in the pyridoneBODIPY in the absence of the fullerene
partner. The small difference in attachment chemistry for the fullerene
did not impact the initial singlet energy transfer. However, the N-methylpyrrolidine bridge did slow both the triplet–triplet
energy transfer and the ultimate relaxation rate of the final triplet
state when compared to an isoxazole-based bridge. The rates of each
step were quantified, and computational predictions were used to complement
the proposed mechanism and energetics. The result demonstrated efficient
triplet sensitization of a strong chromophore that lacks significant
spin–orbit coupling