Kinetics and mechanism of the degradation of the pesticide metsulfuron methyl induced by excitation of iron(iii) aqua complexes in aqueous solutions: steady state and transient absorption spectroscopy studiesDedicated to Dr. Pierre Boule in recognition of his outstanding contribution to the development of photochemistry in aqueous solution.

2004 ◽  
Vol 3 (3) ◽  
pp. 296 ◽  
Author(s):  
Salah Rafqah ◽  
Ahmed Aamili ◽  
Sylvie Nelieu ◽  
Lucien Kerhoas ◽  
Jacques Einhorn ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Steady State ◽  
Aqueous Solutions ◽  
Absorption Spectroscopy ◽  
Transient Absorption ◽  
Kinetics And Mechanism ◽  
Transient Absorption Spectroscopy ◽  
Outstanding Contribution ◽  
Aqua Complexes ◽  
Metsulfuron Methyl

scholarly journals Multiphoton Ionization of Nitrobenzene in Non-Aqueous Solutions: Characterization of the Cation and Ion-Molecule Chemistry

1991 ◽  
Vol 11 (2) ◽  
pp. 83-93 ◽  
Author(s):  
G. Siuzdak ◽  
J. J. Belbruno
Keyword(s):  
Aqueous Solutions ◽  
Absorption Spectroscopy ◽  
Ion Mobility ◽  
Transient Absorption ◽  
Multiphoton Ionization ◽  
Transient Absorption Spectroscopy ◽  
Quantum Yields ◽  
Nanosecond Pulses ◽  
Solvent Molecules

The phenoxy cation has been generated in polar and nonpolar solutions by multiphoton ionization of nitrobenzene using nanosecond pulses of 266 nm and 355 nm light. The ions have been characterized by pulsed conductivity (ion mobility) measurements and transient absorption spectroscopy. The involvement of the phenoxy ion in ion-molecule chemistry with either neutral solute or solvent molecules has also been observed and the photochemical products and quantum yields of the ion-molecule products are presented and compared with the neutral photochemistry results.

Ultrafast carrier dynamics of carbon nanodots in different pH environments

2016 ◽  
Vol 18 (5) ◽  
pp. 3838-3845 ◽  
Author(s):  
Laizhi Sui ◽  
Wuwei Jin ◽  
Suyu Li ◽  
Dunli Liu ◽  
Yuanfei Jiang ◽  
...  
Keyword(s):  
Steady State ◽  
Absorption Spectroscopy ◽  
Transient Absorption ◽  
Surface States ◽  
Carrier Dynamics ◽  
Transient Absorption Spectroscopy ◽  
Carboxyl Groups ◽  
Carbon Nanodots ◽  
Ultrafast Carrier Dynamics ◽  
Ultrafast Carrier

The carboxyl groups in C-dots greatly influence PL of C-dots as emissive surface states based on steady-state and transient absorption spectroscopy.

scholarly journals Dynamic exciton localisation in a pyrene–BODIPY–pyrene dye conjugate

2019 ◽  
Vol 21 (18) ◽  
pp. 9013-9025 ◽  
Author(s):  
Nina Auerhammer ◽  
Alexander Schulz ◽  
Alexander Schmiedel ◽  
Marco Holzapfel ◽  
Joscha Hoche ◽  
...  
Keyword(s):  
Steady State ◽  
Absorption Spectroscopy ◽  
Transient Absorption ◽  
Transient Absorption Spectroscopy ◽  
Time Resolved ◽  
Surface Hopping

The photophysics of a molecular triad consisting of a BODIPY dye and two pyrene chromophores attached in 2-position are investigated by steady state and fs-time resolved transient absorption spectroscopy as well as by field induced surface hopping (FISH) simulations.

Steady-state photochemistry (Pschorr cyclization) and nanosecond transient absorption spectroscopy of twisted 2-bromoaryl ketones

2011 ◽  
Vol 83 (4) ◽  
pp. 841-860 ◽  
Author(s):  
Jarugu Narasimha Moorthy ◽  
Subhas Samanta ◽  
Apurba L. Koner ◽  
Werner M. Nau
Keyword(s):  
Steady State ◽  
Absorption Spectroscopy ◽  
Transient Absorption ◽  
Bond Cleavage ◽  
Transient Absorption Spectroscopy ◽  
Polar Solvents ◽  
Transient Phenomena ◽  
X Ray ◽  
Aryl Radicals ◽  
Aryl Ketones

The steady-state as well as transient absorption spectroscopy of a series of 2-bromo-aryl ketones have been comprehensively examined to gain insights concerning (i) the transient phenomena (absorption spectral attributes as well as lifetimes), (ii) rates of C–Br homolysis, and (iii) the behavior of 2-aroylaryl radicals thus generated. The X-ray crystal structure analyses of selected ketones in which the mesomeric effects operate differently reveal that the two aryl rings are drastically twisted about the C=O bond. The twisting manifests itself in the spectral features of the transients, attributed to triplet–triplet (T–T) absorptions, such that they are not readily comparable in some cases to the transients of parent diaryl ketones that lack the 2-bromo group. By associating triplet decays with C–Br cleavage rates, the absolute rate data have been determined for diverse 2-bromoaryl ketones. With the exception of 2-bromo ketones containing meta-methoxy substituents, all other ketones are found to undergo efficient C–Br bond cleavage with rates of ca. 0.1–1.0 × 108 s–1. For m-methoxy-substituted ketones, intriguingly slower deactivation of the triplets was observed. Based on solvent-dependent variation of the lifetimes (longer lifetimes in polar solvents), intramolecular charge transfer has been proposed. The preparative photochemistry and transient phenomena permit invaluable inferences as to the reactivity of 2-aroylaryl radicals in general. Quantum yield determinations and product analyses reveal that highly electrophilic aryl radicals undergo radical recombination, in a poor hydrogen-donating solvent, almost exclusively (>90 %) in the absence of incentive for stabilization via conversion to π-conjugated hydrofluorenyl radicals. Of course, when the latter is feasible, Pschorr cyclization leads to productive photochemical outcome. Moderately electrophilic radicals that lack stabilization via conversion to hydrofluorenyl radicals lend themselves to intramolecular 1,5-hydrogen shifts in conjunction with the formation of dehalogenated diaryl ketones and cyclized fluorenones (Fls) or its analogs.

Catching metallic nitride endohedral fullerenes in organic and aqueous media

2016 ◽  
Vol 20 (08n11) ◽  
pp. 1025-1033 ◽  
Author(s):  
Volker Strauss ◽  
Shankara Gayathri Radhakrishnan ◽  
Jenny Malig ◽  
Norbert Jux ◽  
Dirk M. Guldi
Keyword(s):  
Steady State ◽  
Absorption Spectroscopy ◽  
Charge Separation ◽  
Transient Absorption ◽  
Aqueous Media ◽  
Transient Absorption Spectroscopy ◽  
Time Resolved ◽  
Endohedral Fullerenes ◽  
Multi Wavelength ◽  
Metallic Nitride

Two bis-tetraphenylporphyrin tweezers-like conjugates bearing different linkers have been characterized by means of electrochemical and photophysical methods. The thrust of this work was the complexation of these bis-porphyrins with C[Formula: see text] and metallic nitride endohedral fullerenes (MNEF) like Sc3N@C[Formula: see text] in organic and in aqueus media — studied by a combination of steady-state and time-resolved spectroscopies. In the context of charge separation evidence for the formation of the 1a[Formula: see text]-Sc3N@C[Formula: see text] and 1c[Formula: see text]-Sc3N@C[Formula: see text] charge separated states in organic and aqueous media, respectively, came from transient absorption spectroscopy. Multi-wavelength analyses afforded charge separated state lifetimes of around 400 ps.

Excited-state photophysical processes in a molecular system containing perylene bisimide and zinc porphyrin chromophores

2020 ◽  
Vol 22 (36) ◽  
pp. 20891-20900
Author(s):  
Fan Yang ◽  
Yanzhou Wu ◽  
Juan Zhao ◽  
Yiting Guo ◽  
Xudong Guo ◽  
...  
Keyword(s):  
Excited State ◽  
Steady State ◽  
Absorption Spectroscopy ◽  
Transient Absorption ◽  
Molecular System ◽  
Transient Absorption Spectroscopy ◽  
Zinc Porphyrin ◽  
Perylene Bisimide ◽  
Photophysical Behavior ◽  
Photophysical Processes

The photophysical behavior of PDI–ZnPor–PDI in both film- and solution-forms has been investigated using steady-state and transient absorption spectroscopy measurements.

scholarly journals Studies of Ultrafast Transient Absorption Spectroscopy of Gold Nanorods in an Aqueous Solution

ACS Omega ◽  
2019 ◽  
Vol 4 (7) ◽  
pp. 12626-12631 ◽  
Author(s):  
Garima Kedawat ◽  
Indu Sharma ◽  
Kanika Nagpal ◽  
Mahesh Kumar ◽  
Govind Gupta ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Absorption Spectroscopy ◽  
Gold Nanorods ◽  
Transient Absorption ◽  
Transient Absorption Spectroscopy ◽  
Ultrafast Transient Absorption ◽  
Ultrafast Transient Absorption Spectroscopy
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