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V L Aksenov - One of the best experts on this subject based on the ideXlab platform.
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non reversible Solvatochromism in n methyl 2 pyrrolidone toluene mixed solutions of fullerene c60
Chemical Physics Letters, 2013Co-Authors: O A Kyzyma, M V Korobov, M V Avdeev, V L Aksenov, L A Bulavin, о T KyreyAbstract:Abstract Non-reversible changes in the UV–Vis spectra (Solvatochromism) of C 60 fullerene in the binary solvent N -methyl-2-pyrrolidone/toluene are observed when varying the mixture composition. The Solvatochromism strongly depends on the order of the mixture preparation. We attribute the effect to a great difference in the polarity of the liquid components, which determines different solvent–solute interaction with respect to the formation of charge-transfer complexes and, thus, provides conditions for selective solvation. The effect is also dependent on the temporal changes in the complexes C 60 – N -methyl-2-pyrrolidone and C 60 cluster formation.
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Non-reversible Solvatochromism in N-methyl-2-pyrrolidone/toluene mixed solutions of fullerene C60
Chemical Physics Letters, 2013Co-Authors: O A Kyzyma, M V Korobov, M V Avdeev, L A Bulavin, T.О. Kyrey, V L AksenovAbstract:Abstract Non-reversible changes in the UV–Vis spectra (Solvatochromism) of C 60 fullerene in the binary solvent N -methyl-2-pyrrolidone/toluene are observed when varying the mixture composition. The Solvatochromism strongly depends on the order of the mixture preparation. We attribute the effect to a great difference in the polarity of the liquid components, which determines different solvent–solute interaction with respect to the formation of charge-transfer complexes and, thus, provides conditions for selective solvation. The effect is also dependent on the temporal changes in the complexes C 60 – N -methyl-2-pyrrolidone and C 60 cluster formation.
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Solvatochromism and fullerene cluster formation in c60 n methyl 2 pyrrolidone
Fullerenes Nanotubes and Carbon Nanostructures, 2010Co-Authors: O A Kyzyma, M V Korobov, M V Avdeev, Vasil M Garamus, V I Petrenko, V L Aksenov, L A BulavinAbstract:UV-Vis spectroscopy and small-angle neutron scattering experiments are performed on the cluster solution of fullerene C60 in N-methyl-2-pyrrolidone before and after dilution of the system with pure solvent. Some changes in the UV-Vis spectra showing Solvatochromism at dilution are observed, while the neutron scattering signal does not change. The effect is discussed with respect to the relation between Solvatochromism and cluster formation for fullerene solutions in nitrogen-containing solvents.
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Solvatochromism and Fullerene Cluster Formation in C60/N-methyl-2-pyrrolidone
Fullerenes Nanotubes and Carbon Nanostructures, 2010Co-Authors: O A Kyzyma, M V Korobov, M V Avdeev, Vasil M Garamus, V I Petrenko, V L Aksenov, L A BulavinAbstract:UV-Vis spectroscopy and small-angle neutron scattering experiments are performed on the cluster solution of fullerene C60 in N-methyl-2-pyrrolidone before and after dilution of the system with pure solvent. Some changes in the UV-Vis spectra showing Solvatochromism at dilution are observed, while the neutron scattering signal does not change. The effect is discussed with respect to the relation between Solvatochromism and cluster formation for fullerene solutions in nitrogen-containing solvents.
Byunghun Choi - One of the best experts on this subject based on the ideXlab platform.
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synthesis and properties of some novel pyrazolone based heterocyclic azo disperse dyes containing a fluorosulfonyl group
Dyes and Pigments, 2012Co-Authors: Ajay Vikram Singh, Ran Choi, Byunghun ChoiAbstract:A series of heteroarylazo disperse dyes derived from pyrazolones and fluorosulfonyl anilines were synthesized, and their thermal and spectral properties were investigated with respect to the effect of substituents on absorption spectra, halochromism, and Solvatochromism. Heteroarylazo disperse dyes, which contain a nitro group instead of a fluorosulfonyl group para to the azo group in the diazo component, were also synthesized for comparative purpose. The fluorosulfonylarylazopyrazolone dyes had absorption maxima at shorter wavelength and showed lower extinction coefficients than the nitroarylazopyrazolone dyes. The synthesized dyes also exhibited positive halochromism and Solvatochromism, so the absorption bands of the dyes moved toward longer wavelengths as the acidity or polarity of the solvent increased. 4-Fluorosulfonyl-substituted dyes generally showed lower thermal stability than their 4-nitro-substituted analogs, because the lower electron-withdrawing power in the diazo components tended to decrease the polarizability and dipole interactions.
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Synthesis and properties of some novel pyrazolone-based heterocyclic azo disperse dyes containing a fluorosulfonyl group
Dyes and Pigments, 2012Co-Authors: Ajay Singh, Ran Choi, Byunghun Choi, Joonseok KohAbstract:A series of heteroarylazo disperse dyes derived from pyrazolones and fluorosulfonyl anilines were synthesized, and their thermal and spectral properties were investigated with respect to the effect of substituents on absorption spectra, halochromism, and Solvatochromism. Heteroarylazo disperse dyes, which contain a nitro group instead of a fluorosulfonyl group para to the azo group in the diazo component, were also synthesized for comparative purpose. The fluorosulfonylarylazopyrazolone dyes had absorption maxima at shorter wavelength and showed lower extinction coefficients than the nitroarylazopyrazolone dyes. The synthesized dyes also exhibited positive halochromism and Solvatochromism, so the absorption bands of the dyes moved toward longer wavelengths as the acidity or polarity of the solvent increased. 4-Fluorosulfonyl-substituted dyes generally showed lower thermal stability than their 4-nitro-substituted analogs, because the lower electron-withdrawing power in the diazo components tended to decrease the polarizability and dipole interactions. © 2012 Elsevier Ltd. All rights reserved.
Nagaiyan Sekar - One of the best experts on this subject based on the ideXlab platform.
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Solvatochromism in organic colorants : An explanatory note
2020Co-Authors: Nagaiyan SekarAbstract:Definition of Solvatochromism, signs of Solvatochromism, physicochemical explanation, and factors affecting Solvatochromism are explained with literature references.
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Fluorescent Benzocoumarin-π-Extended Styryl Hybrids: Solvatochromism, Excess Dipole Moment, NLO Properties and DFT Study
Journal of Fluorescence, 2017Co-Authors: Umesh Warde, Nagaiyan SekarAbstract:Four benzo[h]chromen-3-yl)ethylidene) malononitrilestyryl hybrid dyes are presented for their potential non-linear optical properties using Solvatochromism and density functional theory. The dyes are characterized by 1H and 13C NMR and elemental analysis. They have different donor and same acceptor as dicyanovinyl coumarin. Absorption and emission properties are highly dependent on substituents and environment. Dyes 3a and 3c show absorption Solvatochromism while 3b and 3d show emission Solvatochromism. Solvatochromism is used for the evaluation of excited state dipole moment and nonlinear optical properties which are comparable with the computed values. Limits of hyperpolarizability are close to the experimental and calculated values. Results shows that these dyes having strong intramolecular charge transfer characters proposing their potential nonlinear optical character.
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solvatochromic benzo h coumarins synthesis Solvatochromism nlo and dft study
Optical Materials, 2017Co-Authors: Umesh Warde, Nagaiyan SekarAbstract:Abstract Three benzo[h] coumarins were synthesized and analyzed for their potential NLOphoric properties. Coumarins were synthesized using Knoevenagel condensation method by reacting hydroxyl-naphthalene aldehyde with cyano-methylelene-benzazoles containing NH, O and S elements respectively as the active methylene compounds. The absorption maxima for the coumarins are not affected by the solvent polarity but emission maxima does. Emission Solvatochromism was analyzed using various solvent polarity functions which highlights the polarity dependency of the emission profile. Coumarins showed satisfactory values for first and second hyperpolarizability which are comparable using Solvatochromism and DFT. NLO properties are also compared with the limits of hyperpolarizability calculated using sum rule of quantum mechanics. Results show that the NLO properties predicted by DFT are close to the upper limits of hyperpolarizability. The functional CAM-B3LYP is proven to be suitable for predicting NLO properties for these coumarins compared to functional B3LYP. The present study highlights the importance of such molecules for incorporating in advanced NLOphores.
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Substituent Modulation from ESIPT to ICT Emission in Benzoimidazolphenyl-methanones Derivatives: Synthesis, Photophysical and DFT Study
Journal of Solution Chemistry, 2017Co-Authors: Amol G. Jadhav, Nagaiyan SekarAbstract:Design and synthesis of five new derivatives of benzophenone based imidazole dyes is presented. Synthesized dyes were well characterized by ^1H NMR, ^13C NMR, FT-IR and mass analysis. Dyes contain a secondary acceptor, ESIPT core and different donors forming (D-ESIPT core-A) as basic skeleton in order to study both ESIPT and ICT systematically in this same class of dyes. Dyes without a donor substituent showed ESIPT emission while dyes with a substituted strong donor showed intramolecular charge transfer (ICT) emission. Moreover emission properties of methoxy analogue dyes has been studied to further confirm non-ESIPT emission in dyes without donors and ICT emission in strong donor substituted dyes. All dyes exhibited long range emissions from 392 to 567 nm. Dyes exhibiting ESIPT emission showed negative Solvatochromism while ICT emission exhibiting dyes shows positive Solvatochromism. ICT and ESIPT characteristics are well correlated with polarity functions plots and Mulliken–Hush analysis. Experimental observations are well supported by TD–DFT and computed energies. The electrophilicity index has been calculated to get details of the stabilities of possible tautomers.
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novel pyrazino phenanthroline based rigid donor π acceptor compounds a detail study of optical properties acidochromism Solvatochromism and structure property relationship
Dyes and Pigments, 2017Co-Authors: Shantaram Kothavale, Nagaiyan SekarAbstract:Abstract Donor-π-acceptor-π-auxiliary acceptor type compounds have been designed and synthesized to study their rigidity and structural effects on optical properties. Structural variation is achieved by changing the central π-conjugated core with naphthalene, acenaphthene and phenanthrene based donor-π-acceptor compounds containing N, N -diethyl aniline or morpholine as donor and pyrazine ring fused with phenanthroline as acceptor. A detailed study of positive and negative acidochromism is performed. Intramolecular charge transfer, Solvatochromism and highly polar excited state of these compounds are elucidated by Lippert-Mataga, Mac-Rae and Reichardt correlations. Multilinear regression analysis using Kamlet-Taft and Catalan parameters is also performed to support the observed Solvatochromism in absorption and emission spectra from non-polar to polar solvents. All the spectroscopic results were correlated theoretically by Density Functional Theory (DFT) computations.
O A Kyzyma - One of the best experts on this subject based on the ideXlab platform.
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non reversible Solvatochromism in n methyl 2 pyrrolidone toluene mixed solutions of fullerene c60
Chemical Physics Letters, 2013Co-Authors: O A Kyzyma, M V Korobov, M V Avdeev, V L Aksenov, L A Bulavin, о T KyreyAbstract:Abstract Non-reversible changes in the UV–Vis spectra (Solvatochromism) of C 60 fullerene in the binary solvent N -methyl-2-pyrrolidone/toluene are observed when varying the mixture composition. The Solvatochromism strongly depends on the order of the mixture preparation. We attribute the effect to a great difference in the polarity of the liquid components, which determines different solvent–solute interaction with respect to the formation of charge-transfer complexes and, thus, provides conditions for selective solvation. The effect is also dependent on the temporal changes in the complexes C 60 – N -methyl-2-pyrrolidone and C 60 cluster formation.
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Non-reversible Solvatochromism in N-methyl-2-pyrrolidone/toluene mixed solutions of fullerene C60
Chemical Physics Letters, 2013Co-Authors: O A Kyzyma, M V Korobov, M V Avdeev, L A Bulavin, T.О. Kyrey, V L AksenovAbstract:Abstract Non-reversible changes in the UV–Vis spectra (Solvatochromism) of C 60 fullerene in the binary solvent N -methyl-2-pyrrolidone/toluene are observed when varying the mixture composition. The Solvatochromism strongly depends on the order of the mixture preparation. We attribute the effect to a great difference in the polarity of the liquid components, which determines different solvent–solute interaction with respect to the formation of charge-transfer complexes and, thus, provides conditions for selective solvation. The effect is also dependent on the temporal changes in the complexes C 60 – N -methyl-2-pyrrolidone and C 60 cluster formation.
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Solvatochromism and fullerene cluster formation in c60 n methyl 2 pyrrolidone
Fullerenes Nanotubes and Carbon Nanostructures, 2010Co-Authors: O A Kyzyma, M V Korobov, M V Avdeev, Vasil M Garamus, V I Petrenko, V L Aksenov, L A BulavinAbstract:UV-Vis spectroscopy and small-angle neutron scattering experiments are performed on the cluster solution of fullerene C60 in N-methyl-2-pyrrolidone before and after dilution of the system with pure solvent. Some changes in the UV-Vis spectra showing Solvatochromism at dilution are observed, while the neutron scattering signal does not change. The effect is discussed with respect to the relation between Solvatochromism and cluster formation for fullerene solutions in nitrogen-containing solvents.
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Solvatochromism and Fullerene Cluster Formation in C60/N-methyl-2-pyrrolidone
Fullerenes Nanotubes and Carbon Nanostructures, 2010Co-Authors: O A Kyzyma, M V Korobov, M V Avdeev, Vasil M Garamus, V I Petrenko, V L Aksenov, L A BulavinAbstract:UV-Vis spectroscopy and small-angle neutron scattering experiments are performed on the cluster solution of fullerene C60 in N-methyl-2-pyrrolidone before and after dilution of the system with pure solvent. Some changes in the UV-Vis spectra showing Solvatochromism at dilution are observed, while the neutron scattering signal does not change. The effect is discussed with respect to the relation between Solvatochromism and cluster formation for fullerene solutions in nitrogen-containing solvents.
Joonseok Koh - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and properties of some novel pyrazolone-based heterocyclic azo disperse dyes containing a fluorosulfonyl group
Dyes and Pigments, 2012Co-Authors: Ajay Singh, Ran Choi, Byunghun Choi, Joonseok KohAbstract:A series of heteroarylazo disperse dyes derived from pyrazolones and fluorosulfonyl anilines were synthesized, and their thermal and spectral properties were investigated with respect to the effect of substituents on absorption spectra, halochromism, and Solvatochromism. Heteroarylazo disperse dyes, which contain a nitro group instead of a fluorosulfonyl group para to the azo group in the diazo component, were also synthesized for comparative purpose. The fluorosulfonylarylazopyrazolone dyes had absorption maxima at shorter wavelength and showed lower extinction coefficients than the nitroarylazopyrazolone dyes. The synthesized dyes also exhibited positive halochromism and Solvatochromism, so the absorption bands of the dyes moved toward longer wavelengths as the acidity or polarity of the solvent increased. 4-Fluorosulfonyl-substituted dyes generally showed lower thermal stability than their 4-nitro-substituted analogs, because the lower electron-withdrawing power in the diazo components tended to decrease the polarizability and dipole interactions. © 2012 Elsevier Ltd. All rights reserved.
