Premium
An Ultra‐Long‐Lived Triplet Excited State in Water at Room Temperature: Insights on the Molecular Design of Tridecafullerenes
Author(s) -
RamosSoriano Javier,
PérezSánchez Alfonso,
RamírezBarroso Sergio,
Illescas Beatriz M.,
Azmani Khalid,
RodríguezFortea Antonio,
Poblet Josep M.,
Hally Cormac,
ll Santi,
GarcíaFresnadillo David,
Rojo Javier,
Martín Nazario
Publication year - 2021
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.202104223
Subject(s) - excited state , solvation , quenching (fluorescence) , aqueous solution , triplet state , chemical physics , photochemistry , materials science , chemistry , fluorescence , molecule , atomic physics , optics , physics , organic chemistry
Suitably engineered molecular systems exhibiting triplet excited states with very long lifetimes are important for high‐end applications in nonlinear optics, photocatalysis, or biomedicine. We report the finding of an ultra‐long‐lived triplet state with a mean lifetime of 93 ms in an aqueous phase at room temperature, measured for a globular tridecafullerene with a highly compact glycodendrimeric structure. A series of three tridecafullerenes bearing different glycodendrons and spacers to the C 60 units have been synthesized and characterized. UV/Vis spectra and DLS experiments confirm their aggregation in water. Steady‐state and time‐resolved fluorescence experiments suggest a different degree of inner solvation of the multifullerenes depending on their molecular design. Efficient quenching of the triplet states by O 2 but not by waterborne azide anions has been observed. Molecular modelling reveals dissimilar access of the aqueous phase to the internal structure of the tridecafullerenes, differently shielded by the glycodendrimeric shell.