Solvent effects on photophysical parameters for coumarin laser dyes

Excited-state hydrogen bonding effect on dynamic fluorescence of coumarin 102 chromophore in solution: A time-resolved fluorescence and theoretical study

“…Therefore, the hydrogen-bond dynamics between courmarin 102 and hydroxylic solvents has been widely studied [37][38][39][40][41][42][43][44][45][46]. According to the reports by Jones II et al [41,42], coumarin dyes would exhibit notable redshifts in their steadystate spectra due to the polarity and site-specific effect of solvents. Therefore, it is significant to investigate the hydrogenbonded thermodynamic equilibrium in electronic excited states, since the equilibrium shift caused by excited-state hydrogen bond plays an important role in photochemical behavior [44,46].…”

Structure of 7-dimethylamino-4-trifluoromethylcoumarin

“…Aminocoumarins, which are used as laser dyes for the blue-green spectral region (Drexhage, 1973), vary in their photophysical properties for different kinds of chemical substitutions (Jones, Jackson & Kanoktanaporn, 1980;Jones, Jackson, Choi & Bergmark, 1985;Masilamani, Sastikumar, Natarajan & Natarajan, 1987). The title compound (Fig.…”

Calculating singlet excited states: Comparison with fast time-resolved infrared spectroscopy of coumarins

“…56 Lower fluorescence quantum yields in highly polar solvents have been attributed to the formation of a separate, low-lying, twisted intramolecular charge transfer (TICT) S 1 state in 7-aminocoumarins containing flexible alkyl-substituted 7-NH 2 groups. 48,[54][55][56][57] This has been supported by TDDFT calculations, 58 and appears to require range-separated functionals for a correct description within TDDFT. 58 Furthermore, the conformational flexibility of these systems may also influence the IR spectra.…”