Tuning Interactions to Control Molecular Down Conversion in [2.2]Paracyclophane Bridged Oligo-Tetracenes
Rapp MR, Weiß R, Wollny AS, Guldi DM, Bettinger HF (2024)
Publication Type: Journal article
Publication year: 2024
Journal
Abstract
In tetracene, the energies of the lowest singlet excited state and twice that of the lowest triplet excited state are similar, allowing both down-conversion (i.e., singlet fission, SF) and up-conversion (i.e., triplet-triplet annihilation up-conversion, TTA-UC) processes. Through-space and through-bond contributions to the inter-tetracene coupling in purposefully designed oligomers play a crucial role in determining which of the two processes dominates. In this work, the focus is exclusively on SF in newly synthesized oligo-tetracenes linked by conjugated [2.2]paracyclophane (PCP) building blocks. By choosing different PCP substitution patterns and by varying the degree of substitution the inter-tetracene couplings are addressed. An independent variable is connecting the tetracences to the PCP at different positions to alter the through-bond and through-space coupling of the resulting oligo-tetracenes. The novel oligo-tetracenes are investigated by means of steady-state and time-resolved absorption and fluorescence spectroscopies with respect to the initial events of SF, that is, the transformation of a singlet excited state into a correlated triplet pair state. Briefly, through-space couplings are profoundly weaker than through-bond couplings that enable the correlated triplet pair state formation. If interactions are through-space, correlated triplet pair state formation is turned off, while it is turned on if through-bond interactions are operative.
Authors with CRIS profile
René Weiß
Lehrstuhl für Physikalische Chemie I
Anna-Sophie Wollny
Lehrstuhl für Physikalische Chemie I
Dirk Michael Guldi
Lehrstuhl für Physikalische Chemie I
Involved external institutions
Germany (DE)How to cite
APA:
Rapp, M.R., Weiß, R., Wollny, A.-S., Guldi, D.M., & Bettinger, H.F. (2024). Tuning Interactions to Control Molecular Down Conversion in [2.2]Paracyclophane Bridged Oligo-Tetracenes. Advanced Functional Materials. https://dx.doi.org/10.1002/adfm.202313576
MLA:
Rapp, Mario R., et al. "Tuning Interactions to Control Molecular Down Conversion in [2.2]Paracyclophane Bridged Oligo-Tetracenes." Advanced Functional Materials (2024).
BibTeX: Download