Glossary of Terms used in Photochemistry

Braslavsky, Silvia E.; Thulstrup, Erik W.; Acuna, U.; Armesto, D.; Atvars, T. D. Z.; Bard, A.; Bill, E.; Björn, L. O.; Bohne, C.; Bolton, J P R; Bonneau, R.; Bouas‐Laurent, Henri; Braun, André M.; Dale, Russell C.; Dill, K.; Dürr, Heinz; Fox, Malcolm A.; Gandolfi, T.; Grabowski, Zbigniew R.; Griesbeck, Axel G.; Kutateladze, A.; Litter, Marta I.; Lorimer, John W.; Michl, J.; Miller, R. J. Dwayne; Moggi, L.; Monti, S.; Nonell, S.; Ogilby, P.; Olbrich, G.; Oliveros, E.; Olivucci, M.; Prokorenko, V.; Naqvi, K. Razi; Rettig, W.; Rizzi, Alberto Claudio; Román, E. San; Scandola, F.; Schneider, Stephen H.; Valeur, B.; Verhoeven, J. W.; Warman, J.; Weiss, Roberta C.; Wirz, J.; Zachariasse, K.

doi:10.1016/b978-044451322-9/50034-8

Cited by 164 publications

(185 citation statements)

References 0 publications

Supporting

Mentioning

180

Contrasting

Unclassified

Order By: Relevance

“…Using the values of the molar absorption coefficient ε max at λ abs (max) and the fluorescence quantum yield Φ, the brightness (defined as the product ε(λ abs ) × Φ) 25 for a selection of dyes/solvents was exemplarily computed. The maximum values of the brightness for 2, 3 and 11 in methanol, THF and toluene are given in Table 2 and prove that compounds 2 and 3 (without a nitro group) are definitely bright fluorophores.…”

Section: Spectroscopic and Photophysical Propertiesmentioning

confidence: 99%

UV—vis spectroscopy of the coupling products of the palladium-catalyzed C—H arylation of the BODIPY core

Wang

Verbelen

Tonnelé

et al. 2013

Photochem Photobiol Sci

View full text Add to dashboard Cite

The steady-state, UV-vis electronic absorption and fluorescence emission properties of a large set of 3-aryl and 3,5-diaryl substituted difluoroboron dipyrromethene dyes obtained via direct, palladiumcatalyzed C-H (het)arylation of the BODIPY core are reported. The spectra display the narrow absorption and fluorescence emission bands and the generally quite small Stokes shifts characteristic of classic difluoroboron dipyrrins. As a function of the solvent, the spectral maxima are located within a very narrow wavelength range and are slightly red-shifted with increasing solvent polarizability, which is shown to be the crucial parameter influencing the wavelength position of the maxima. The extended π-conjugation in the 3,5-diaryl products always leads to bathochromically shifted absorption and emission spectra compared to those of the 3-aryl analogues. The derivative with a 3-mesityl substituent has blue-shifted spectra in comparison to its 3-phenyl substituted analogue, reflecting the diminished π-conjugation in the former due to steric strain. The nature of the meso-aryl has only a small effect on the spectral positions but affects the fluorescence quantum yield Φ. The majority of the dyes have high Φ (>0.85), except the compounds with meso-phenyl and meso-( p-nitrophenyl) substituents. Quantumchemical calculations were performed to evaluate the differences in spectroscopic properties upon substitution of the BODIPY core and to compare them with the corresponding experimental results.

show abstract

Section: Spectroscopic and Photophysical Propertiesmentioning

confidence: 99%

UV—vis spectroscopy of the coupling products of the palladium-catalyzed C—H arylation of the BODIPY core

Wang

Verbelen

Tonnelé

et al. 2013

Photochem Photobiol Sci

View full text Add to dashboard Cite

show abstract

“…1, 2 Diarylethenes are typical photochromic molecules in which the thermodynamically stable colorless open-ring isomer is converted to the colored closed-ring isomer upon irradiation (see, for example, Scheme 1), while the reverse reaction is either thermally or photochemically activated. 3,4…”

Section: Introductionmentioning

confidence: 99%

Photochemical investigation of a photochromic diarylethene compound that can be used as a wide range actinometer

Santos

Ballardini

Belser

et al. 2009

Photochem Photobiol Sci

View full text Add to dashboard Cite

The photochromic diarylethene derivative 1,2-bis(5-(4-ethynylphenyl)-2-methylthiophen-3-yl)perfluorocyclopentene (1) was submitted to photochemical, thermal stability and fatigue resistance studies in acetonitrile, also to evaluate its possible application as a new actinometer. This photochromic system covers a wide spectral absorption range, with intense bands in the UV and visible regions for the open-ring and closed-ring isomers, respectively. Very high ring-closure quantum yield values were obtained, in contrast with the low ring-opening quantum yields, which are nevertheless high enough to exploit 1 as an actinometer. The procedure required to determine the photon flux of an irradiation source with this fatigue resistant compound is indeed very simple.

show abstract

“…Therefore, it is Φ Substrate = R Substrate (P a MCPA ) −1 . The absorbed photon flux can be calculated from the spectral data, (Braslavsky, 2007), where p°(λ) is the incident spectral photon flux density (it is reported as the lamp emission spectrum in Figure 1 The importance of the direct photolysis and of the reaction with • OH for the degradation of MCPA in surface waters were compared by means of a modelling approach. Based on recently developed models (Vione et al, 2009a;2009b), the half-life time of MCPA upon direct photolysis would be:…”

Section: Calculations and Data Treatmentmentioning

confidence: 99%

Effect of dissolved organic compounds on the photodegradation of the herbicide MCPA in aqueous solution

Vione

Khanra²,

Das³

et al. 2010

Water Research

View full text Add to dashboard Cite

This works shows that the addition of phenol and 2-propanol as model organic compounds significantly decreases the direct photolysis quantum yield of 4-chloro-2-methylphenoxyacetic acid (MCPA) upon UVB irradiation in aqueous solution. Laser flash photolysis data suggest that 2-propanol is able to decrease the formation of the MCPA excited states under irradiation. A decrease from 0.54 to 0.34 of the photolysis quantum yield of the anionic form of MCPA (which prevails over the undissociated one in surface waters) could have a considerable impact on the MCPA lifetime in ecosystems where the direct photolysis is the main phototransformation pathway. In surface water bodies where the direct photolysis has comparable kinetics as the reaction with • OH, a decrease of the quantum yield would enhance the relative importance of the • OH pathway, which yields considerably less toxic intermediates than the direct photolysis.

show abstract

Glossary of Terms used in Photochemistry

Cited by 164 publications

References 0 publications

UV—vis spectroscopy of the coupling products of the palladium-catalyzed C—H arylation of the BODIPY core

UV—vis spectroscopy of the coupling products of the palladium-catalyzed C—H arylation of the BODIPY core

Photochemical investigation of a photochromic diarylethene compound that can be used as a wide range actinometer

Effect of dissolved organic compounds on the photodegradation of the herbicide MCPA in aqueous solution

Contact Info

Product

Resources

About