RT Journal Article
T1 Generation of multiple triplet states in an orthogonal bodipy dimer: a breakthrough spectroscopic and theoretical approach
A1 García Moreno, Inmaculada
A1 Postils, Verónica
A1 Rebollar, Esther
A1 Ortíz García, María Josefa
A1 Rodríguez Agarrabeitia, Antonia
A1 Casanova, David
AB Generation of triplet states in assemblies of organic chromophores is extremely appealing for their potential use in optoelectronic applications. In this work, we investigate the intricacies of triplet state generation in an orthogonal BODIPY dimer by combining delayed photoemission techniques with electronic structure calculations. Our analysis provides a deep understanding of the electronic states involved, and describes different competing deactivation channels beyond prompt radiative decay. In particular, we identify charge-transfer (CT) mediated intersystem crossing (ISC) as the most likely mechanism for the triplet state generation in this system. The different emission bands at long times can be associated with delayed fluorescence, CT emission and phosphorescence from multiple low-energy triplets. Interestingly, the dependence of the yield of triplet state population and emission profiles with the solvent polarity evidences the decisive role of the CT configuration in the fate of the photoactivated dimer, controlling the relative ISC, reverse ISC, and internal conversion efficiencies. Overall, the present results provide a rather complete description of the delayed photophysics in the BODIPY dimer, but are not able to fully rationalize the unexpected photoluminescence recorded at long wavelengths (≥ 900 nm). We hypothesize that the origin of this emission, not present in BODIPY monomers, emerges from intermonomer interactions triggered by intramolecular distortions opening up a new vision in the controverted mechanism driving the photophysical behavior from orthogonally linked organic monomers.
PB Royal Society of Chemistry
SN 1463-9076
YR 2022
FD 2022-02-14
LK https://hdl.handle.net/20.500.14352/71851
UL https://hdl.handle.net/20.500.14352/71851
LA eng
NO Submitted: 15 Dec 2021; Accepted: 14 Feb 2022; First published	: 14 Feb 2022
NO Ministerio de Ciencia e Innovación (MICINN)
NO Gobierno Vasco
NO Universidad del País Vasco
DS Docta Complutense
RD 6 may 2024