Concentration quenching in fluorescent acene solutions

Highly sensitive thermal damage sensors for polymer composites: time temperature indicator based on thermochromic fluorescence turn-on response

“…As the powdered M1 dissolves completely in MEK, which is miscible in Sylgard A and B, the initial distribution of the M1 molecules is considered to be constant throughout the liquid batch. The concentration of 0.1 wt% was sufficient to give strong fluorescent emission but low enough to avoid aggregation induced quenching issues, which are known to affect fluorescent molecules of the anthracene family [43][44][45]. The liquid components were mixed by hand for ∼5 min and held under 28 mmHg vacuum for 30 min, then held at 70 °C for ∼2 h in a drying oven to evaporate MEK.…”

Effects of the Environment on the Fluorescence of Aromatic Compounds in Solution.

“…The fluorescence efficiency (F0) is the ratio of the number of light quanta absorbed to the number of light quanta emitted and there are formidable instrumental and experimental difficulties which have to be overcome in its measurement (18,25,108). Many measurements have been made of the quantum yield of fluorescence (18,24,25,26,37,43,65,108,183) and these measurements are of significance in the study of fluorescence quenching either by internal conversion or intersystem crossing (i.e., singlet-triplet transitions) and in the examination of transfer of electronic excitation energy. The fluorescence efficiency which is an inherent property of a compound is influenced by solvent, temperature, and concentration.…”

Some correlations of aromatic decomposition G values

“…A less efficient deactivation, with a correspondingly less efficient interaction, is implied by the rate constant for the collisional deactivation by benzene molecules of the 1BzU excited state of benzene, which is 5 x 10-13 cm3 molecule-1 sec-1 for concentrations up to -1.0 M benzene in n-hexane. 22 (Compared with such collisional deactivation, it was shown in addition that conversion to the ground state by fluorescence and intramolecular quenching would be negligible at concentrations of 1 M benzene and above.) However, comparisons23 of the fluorescence efficiencies of scintillator solutions in benzene with ultra-violet light and 60Co yradiation show that G(lBzu) is as low as 0.2-0.5.…”