Fluorescence decay times of cyclic ketones, acetone, and butanal in the gas phase

Photochemical and photophysical study on the kinetics of the atmospheric photodissociation of acetone

“…The fluorescence quantum yield has a slight wavelength dependence, therefore using Thurber's [14] formulae, a value of Φ f = 0.00096 can be estimated from our quantum yield measurements to the 296 nm excitation wavelength, where the lifetime determination was conducted. The derived k f = Φ f × 1 τ -1 = (3.7 ± 0.7) 10 5 s -1 shows good agreement with the recent determination by Koch et al [18] (k f = 3 10 5 s -1 ), and is definitely lower than that published before [17,[19][20] based on moderately higher fluorescence yields [20][21]. Utilising this new radiative rate constant together with the spectra shown in Fig.…”

Measurements and modeling of acetone laser-induced fluorescence with implications for temperature-imaging diagnostics

“…The model was applied in an effort to explain the various photophysical results observed for acetone. These results include published data from which radiationless electronic relaxation rates can be extracted as a function of excited singlet energy E, 13,28,38 published data describing the pressure dependence of acetone fluorescence, 12,13 and the fluorescence-yield temperature-dependence data presented above in this paper. Pressure data sets for gas mixtures that include oxygen are not for the moment considered in model comparisons because of possible unique effects of oxygen at high pressure.…”

“…A biexponential expression for k NR ͑E͒ was chosen for use with the model. The first two sources of comparison data, the studies of Breuer and Lee 38 and Ossler and Aldén, 13 provide low-pressure fluorescence lifetime data for acetone. Based on the premise that the intersystem crossing rate limits the fluorescence lifetime, and on Fig.…”

“…Two slightly off-optimum model cases are also plotted ͑dashed and dotted curves͒. Low-pressure data on fluorescence lifetime ͑Breuer and Lee, 38 Ossler and Aldén 13 ͒ and fluorescence yield ͑Shortridge et al 28 ͒ have been converted into data for k NR ͑E͒, the electronic relaxation rate as a function of vibrational energy, under the assumption of a constant fluorescence rate k f . Biexponential behavior of k NR was assumed in the model ͑see Table 1͒.…”

Fluorescence and phosphorescence of acetone in neat liquid and aqueous solution studied by QM/MM and PCM approaches

“…To model the liquid phases we perform classical MD simulations of acetone in the electronic ground state (GS) as well as in the singlet and triplet excited states (ES) in neat liquid and aqueous solution. We can safely assume a vibrational relaxation of the solute in the ES, since the lifetimes for the singlet and triplet n π* states of acetone in gas phase and solution have been reported to be around 2 ns31–33 and 20 μ s34–36, respectively. Currently, our QM/MM implementation does not allow to consider ES's explicitly.…”