Alcázar, JacksonGarcía-Río, LuisRobles, Agustín I.Dinamarca-Villarroel, LuisFierro, AngélicaSantos, José G.Aliaga, Margarita E.2023-04-262023-04-262023Jackson J. Alcázar, Luis García-Río, Agustín I. Robles, Luis Dinamarca-Villarroel, Angélica Fierro, José G. Santos, Margarita E. Aliaga, Linear relationship between emission quantum yield and Stokes shift in 3-styryl aza-coumarin based dyes in the presence of cyclodextrins, Journal of Molecular Liquids, Volume 381, 2023, 121790, ISSN 0167-7322, https://doi.org/10.1016/j.molliq.2023.121790.https://repositorio.udd.cl/handle/11447/7408The effect of the cyclodextrins inclusion on the Stokes shifts and emission quantum yield of three 3-styryl aza-coumarin dyes (SACs) was experimentally and theoretically studied. Preliminary results show a relationship between the emission quantum yield and the calculated binding constants. Supramolecular inclusion was supported by changes in the fluorescence spectra, high-resolution mass spectrometry and molecular dynamics studies. 2,6-di-O-methyl-b-cyclodextrin (DM-b-CD) presented higher binding constants than b-cyclodextrin (b-CD), along with up to a 6-fold increase in emission quantum yield for the SACs. Additionally, a linear negative correlation was obtained between the Stokes shift and the emission quantum yield. This linear and empirical relationship was explained by the action of a unique intramolecular rotation and charge transfer phenomenon in the dyes, which was modulated by cyclodextrins, and supported by calculations based on density functional theory.9 p.enAza-Coumarin dyesIntramolecular rotationIntramolecular charge transferCyclodextrin inclusionEmission quantum yieldStokes shiftSupramolecular chemistryArticle