Naslov
Tuning the Nature of the Fluorescent State: A Substituted Polycondensed Dye as a Case Study

Autori
Sissa, Cristina ; Calabrese, Valentina ; Cavazzini, Marco ; Grisanti, Luca ; Terenziani, Francesca ; Quici, Silvio ; Painelli, Anna

Izvornik
Chemistry - A European Journal (0947-6539) 19 (2012), 3; 924-935

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
charge transfer ; excited state ; optical properties ; essential-state models ;

Sažetak
An extensive spectroscopic analysis is presented of an elongated polycondensed dye with a donor–acceptor substitution. The charge‐transfer (CT) state, polarized along the long molecular axis, is close in energy to a local excitation (LE) of the polycondensed system, roughly polarized along the short molecular axis, which makes this system particularly suitable to investigate the subtle LE/CT interplay. An essential‐state model is presented that quantitatively reproduces absorption and fluorescence spectra, as well as fluorescence emission and excitation anisotropy spectra collected in solvents of different polarity and viscosity, which sets a sound basis for the understanding of how solvent polarity and solvent relaxation affect the nature of low‐lying excitations. The markedly different fluorescence emission and excitation anisotropy spectra measured in glassy and liquid polar solvents unambiguously demonstrate the major role played by solvent relaxation in the definition of fluorescence properties of the dye.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

POVEZANOST RADA