Spectroscopic Studies on Dyes. IV. The Fluorescence Spectra of Thioindigo Dyes1

1957 ◽  
Vol 79 (10) ◽  
pp. 2464-2468 ◽  
Author(s):  
Delbert A. Rogers ◽  
J. David Margerum ◽  
George M. Wyman
Keyword(s):  
Fluorescence Spectra ◽  
Spectroscopic Studies

scholarly journals Spectroscopic Studies of Dual Fluorescence in 2-(4-Fluorophenylamino)-5-(2,4-dihydroxybenzeno)-1,3,4-thiadiazole: Effect of Molecular Aggregation in a Micellar System

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2861 ◽  
Author(s):  
Grzegorz Czernel ◽  
Arkadiusz Matwijczuk ◽  
Dariusz Karcz ◽  
Andrzej Górecki ◽  
Agnieszka Niemczynowicz ◽  
...  
Keyword(s):  
Light Scattering ◽  
Fluorescence Spectra ◽  
Single Photon ◽  
Spectroscopic Studies ◽  
Fluorescence Probes ◽  
Molecular Aggregation ◽  
Micellar System ◽  
Dual Fluorescence ◽  
Fluorescence Measurements ◽  
Ionic Detergent

The article presents the results of spectroscopic studies focused on a selected compound from the 1,3,4-thiadiazole group—2-(4-fluorophenylamino)-5-(2,4-dihydroxybenzeno)-1,3,4-thia-diazole (FABT)—in a micellar system formed by Triton X-100, a non-ionic detergent. Fluorescence measurements revealed the phenomenon of dual fluorescence whose emergence is related to the particular molecular organisation of the compound, which depends both on the concentration of the detergent and, most of all, the concentration of the compound itself. Dual fluorescence of FABT in a micellar system was observed for the compound dissolved in a methanol aqueous system, i.e., an environment wherein the dual fluorescence of the compound had never been reported before. Based on the interpretation of UV-Vis electronic absorption, resonance light scattering (RLS), emission and excitation fluorescence spectra, as well as measurements of dynamic light scattering (DLS) and Principal Component Analysis (PCA), we were able to relate the occurrence of this effect to the process of molecular aggregation taking place between FABT molecules in the micellar system in question. Results of fluorescence spectra measurements and time-correlated single photon counting (TCSPC) indicate that dual fluorescence occurs at detergent concentrations necessary to form micellar systems, which in turn facilitate the process of aggregation of FABT molecules. The correlation between the observed fluorescence effects and the previous measurements performed for analogues from this group suggests the possibility of charge transfer (CT) within the range of detergent concentrations wherein the aforementioned fluorescence effects are observed. It ought to be emphasised that this type of fluorescence effects are relatively easy to induce, which predisposes this groups of fluorophores as ideal fluorescence probes in the context of biological samples.

Spectroscopic Studies of Dimethylamino Derivatives of Fluorene

2000 ◽  
Vol 55 (11-12) ◽  
pp. 902-908 ◽  
Author(s):  
J. Heldt ◽  
J. R. Heldt ◽  
T. Redzimski ◽  
H. Diehl ◽  
P. Schultz
Keyword(s):  
Dipole Moment ◽  
Excited State ◽  
Charge Transfer ◽  
Fluorescence Spectra ◽  
Intramolecular Charge Transfer ◽  
Stokes Shift ◽  
Spectroscopic Studies ◽  
Polar Solvents ◽  
Derivatives Of ◽  
Transfer State

Abstract 2-dimethylamino-9-fluorenol and 2-dimethylamino-9(4'dimethylamino)phenyl-9-fiuorenol in polar solvents in the excited state undergo conformation changes in which two fluorescent isomers are created. The isomers (in the local excited (LE) and charge transfer (CT) configuration) possess separate fluorescence bands, one appearing from the S1 (LE) state and the second from the intramolecular charge transfer state S1 (CT) of the neutral, aromatic molecule. Both bands show a solvatochromic effect. Using the method of the solvent induced Stokes shift of the absorption and fluorescence spectra the permanent dipole moment of the excited state of fluorene and its two derivatives have been determined. The dipole moment of the ground state and the Onsager cavity radius of the studied molecules were calculated with the Auestion Model 1 (AM1) program.

Spectroscopic Studies of the Energy Levels of the Nd3+ Ion in Single Crystals of SrO.6Al2O3

1988 ◽  
Vol 41 (4) ◽  
pp. 549 ◽  
Author(s):  
H Tajalli
Keyword(s):  
Raman Spectroscopy ◽  
Fluorescence Spectra ◽  
Energy Levels ◽  
Selective Excitation ◽  
Spectroscopic Studies ◽  
Solid State Laser ◽  
Host Lattice ◽  
Absorption And Fluorescence Spectra ◽  
Excitation Spectra ◽  
Laser Material

A detailed study of the polarised absorption and fluorescence spectra and the selective excitation spectra of the Nd3+ ion in the SrO.6Al20 3 host lattice was carried out over the temperature range 4�2 to 500 K. The empirical energy level schemes were determined for two dominant sites of Nd3+ in SrO.6Al20 3 up to 20000 cm -1. The intensity, linewidth and thermal shifts of the transition lines with 4f3 configuration were investigated. The vibrational transitions of Nd3 + : srO.6Al20 3 were also investigated using Raman spectroscopy. The results of the study provide information on the suitability of Nd3+ : srO.6Al20 3 as a solid state laser material.

Fluorescence Spectroscopic Studies of Interaction between 4-Aminobenzenesulfonic Acid and Bovine Serum Albumin

2011 ◽  
Vol 233-235 ◽  
pp. 2619-2623
Author(s):  
Jian Li Liu ◽  
Xiang Yu Cao ◽  
Xiu Li Lu ◽  
Ya Peng Huo
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Fluorescence Spectra ◽  
Radiation Energy ◽  
Entropy Change ◽  
Spectroscopic Studies ◽  
Van Der Waals Interactions ◽  
Synchronous Fluorescence Spectra ◽  
Thermodynamic Equations

The interaction between 4-aminobenzenesulfonic acid and bovine serum albumin (BSA) had been studied by fluorescence spectroscopy. The binding constant (K=2.51×104) and binding points (n=0.998) of 4-aminobenzenesulfonic acid with BSA were determined at 298 K based on fluorescence quenching results. The thermodynamic parameters such as enthalpy change (ΔH), entropy change (ΔS) and Gibbs free-energy change (ΔG) for the reactions were also calculated according to the thermodynamic equations. The negative ΔH and ΔS values in case of 4-aminobenzenesulfonic acid-BSA complexes showed that van der Waals interactions and hydrogen bonds might play a major role in the binding of 4-aminobenzenesulfonic acid to BSA. The distance, r, between donor (BSA) and acceptor (4-aminobenzenesulfonic acid) was obtained according to the Förster’s theory of non-radiation energy transfer. The results of synchronous fluorescence spectra revealed that 4-aminobenzenesulfonic acid induced conformational change of BSA.

Spectroscopic properties of the Pr3+ ion in TeO2-WO3-PbO-La2O3 and TeO2-WO3-PbO-Lu2O3 glasses

Open Physics ◽  
2014 ◽  
Vol 12 (1) ◽  
Author(s):  
Bożena Burtan ◽  
Maciej Sitarz ◽  
Radosław Lisiecki ◽  
Witold Ryba-Romanowski ◽  
Piotr Jeleń ◽  
...  
Keyword(s):  
Refractive Index ◽  
Dispersion Relation ◽  
Fluorescence Spectra ◽  
Tellurite Glass ◽  
Spectroscopic Properties ◽  
Spectroscopic Studies ◽  
Luminescence Decay ◽  
Absorption And Fluorescence Spectra ◽  
Ofelt Theory ◽  
Glass Matrices

AbstractThe goal of this work was to investigate the spectroscopic properties of Pr3+ ions, embedded in two different tellurite glass matrices, TeO2-WO3-PbO-La2O3 and TeO2-WO3-PbO-Lu2O3. The absorption and fluorescence spectra have been recorded and analyzed in terms of the Judd-Ofelt theory along with the luminescence decay of the 3P0 and 1D2 levels of the Pr3+ ion. The spectroscopic studies were completed with ellipsometric measurements providing the dispersion relation of the refractive index of the investigated glasses.

scholarly journals Evaluation of Fluorescent Analogs of Deoxycytidine for Monitoring DNA Transitions from Duplex to Functional Structures

2011 ◽  
Vol 2011 ◽  
pp. 1-7
Author(s):  
Yogini P. Bhavsar ◽  
Samantha M. Reilly ◽  
Randy M. Wadkins
Keyword(s):  
Fluorescence Spectra ◽  
Helical Structure ◽  
Spectroscopic Studies ◽  
Structural Transitions ◽  
Fluorescent Properties ◽  
Common Pathway ◽  
Dna Structures ◽  
Functional Dna ◽  
Lifetime Studies ◽  
Affect Gene Expression

Topological variants of single-strand DNA (ssDNA) structures, referred to as “functional DNA,” have been detected in regulatory regions of many genes and are thought to affect gene expression. Two fluorescent analogs of deoxycytidine, Pyrrolo-dC (PdC) and 1,3-diaza-2-oxophenoxazine (t), can be incorporated into DNA. Here, we describe spectroscopic studies of both analogs to determine fluorescent properties that report on structural transitions from double-strand DNA (dsDNA) to ssDNA, a common pathway in the transition to functional DNA structures. We obtained fluorescence-detected circular dichroism (FDCD) spectra, steady-state fluorescence spectra, and fluorescence lifetimes of the fluorophores in DNA. Our results show that PdC is advantageous in fluorescence lifetime studies because of a distinct ~2 ns change between paired and unpaired bases. However, t is a better probe for FDCD experiments that report on the helical structure of DNA surrounding the fluorophore. Both fluorophores provide complementary data to measure DNA structural transitions.

Synthesis of Fluorine-Containing Tetraarylanthracenes via Ruthenium-Catalyzed C–O or C–F Arylation and their Crystal Structures

Synlett ◽  
2017 ◽  
Vol 28 (19) ◽  
pp. 2609-2613 ◽  
Author(s):  
Fumitoshi Kakiuchi ◽  
Akiko Izumoto ◽  
Hikaru Kondo ◽  
Takuya Kochi
Keyword(s):  
Solid State ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
Fluorescence Spectra ◽  
Crystal Packing ◽  
Spectroscopic Studies ◽  
Carbonyl Groups ◽  
X Ray Diffraction ◽  
Aromatic Ketones ◽  
X Ray

Tetraarylanthracenes containing several fluoro groups were synthesized using the ruthenium-catalyzed C–O or C–F arylation with arylboronates and their structural and spectroscopic studies were conducted. The RuH2(CO)(PPh3)3-catalyzed C–O arylation of aromatic ketones was found to be effective for the introduction of aryl groups containing multiple fluoro groups. Anthracenes possessing fluorinated aryl groups were prepared in two steps from 1,4,5,8-tetramethoxyanthraquinone by C–O arylation and reduction of the carbonyl groups. A tetraphenylanthracene containing a fluorinated anthracene moiety was also prepared using C–F phenylation of octafluoroanthraquinone. Single-crystal X-ray diffraction analysis showed that the positions of fluoro groups on the tetraarylanthracenes lead to notable difference in the crystal packing structures. The larger difference between the tetraarylanthracenes was observed in the fluorescence spectra in the solid state than those in chloroform.

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