Solvent effect on the non-radiative S2(ππ*) decay of xanthione

Photophysics of a fluorescent non-natural amino acid: p-Cyanophenylalanine

“…As a result, k nr also shows a clear dependence on the Kamlet-Taft α parameter where a larger α corresponds to a slower non-radiative decay rate, while k r is much less sensitive to solvent (Figure 5). These results are consistent with the observation that the absorption and emission spectral profiles and the molar absorptivity of Phe CN at wavelengths longer than 260 nm are insensitive to solvent, which may indicate that it is mainly the non-radiative decay channels that are affected by the solute-solvent interactions [26,27]. However, the observed trend for k nr herein is somewhat unusual as a stronger interaction with solvent is often expected to result in a faster non-radiative decay rate of the excited state, as observed for cyano substituted indolines [28].…”

Resonance Raman spectroscopic and density functional theory investigation of the excited state structural dynamics of 2‐mercapto‐1‐methylimidazole

“…The electronic excited state structures, [1][2][3][4][5] decay dynamics [6][7][8][9] and solvent effects [10][11][12][13][14][15] have been reported. The relaxation of the second excited singlet states S 2 (pp*) was governed by a solvent-dependent non-radiative process.…”

“…The relaxation of the second excited singlet states S 2 (pp*) was governed by a solvent-dependent non-radiative process. [10,13] Strong chemical interaction was found between the excited states of thione conformer and hydrocarbon solvent in the process of intermolecular photochemistry and photophysics. [11,13] The ground and excited state geometry structures of thiourea, one of the simplest thiocarbonyl compounds, and its derivatives were determined from the theoretical calculations and experimental measurements.…”

“…Thiocarbonyl compounds, in the last two decades, have been a topic among many theoretical and experimental researchers due to its importance in biology, pharmaceutics and fluorescence sensors. The electronic excited state structures, decay dynamics and solvent effects have been reported. The relaxation of the second excited singlet states S 2 (ππ*) was governed by a solvent‐dependent non‐radiative process .…”

Sn-state lifetime determination of dyes

“…S2-state lifetimes in the picosecond [11][12][13][14][15][16][17][18] and nanosecond regions [19][20][21] have been found in only a few dye molecules. The conventional technique of lifetime determination by fluorescence quantum yield measurement after single-step dye excitation is limited to quantum yields qF = Tp/r^a £ 10" 3 (fluorescence lifetime rF £ 10 ps; r^, radiative lifetime).…”