Time filter

Source Type

Tretiakov M.,University of Gottingen | Shermolovich Y.G.,Institute of Organic Chemistry NAS of Ukraine | Singh A.P.,University of Gottingen | Samuel P.P.,University of Gottingen | And 4 more authors.
Dalton Transactions | Year: 2013

Oxidation reactions of stable chalcogenamides with iodine are intriguing due to their broad application in various organic syntheses. In the present study we report on the utilization of N-heterocyclic carbene and cyclic-alkyl-amino carbenes L1-3: (L1: =:C[N(2,6-iPr 2-C6H3)CH]2, L2: =:C(CH2)(CMe2)(C6H10)N-2,6-iPr 2-C6H3, L3: =:C(CH 2)(CMe2)2N-2,6-iPr2-C 6H3) for the syntheses of chalcogenamides L1-3E (E = S, Se, Te) 1-4 and zwitterionic adducts L1-3E-I-I 5-8. The synthesis of compounds 1-4 involved the addition reaction of ligand L 1-3: and elemental chalcogen. Treatment of 1-4 with iodine resulted in the formation of adducts 5-8. Compounds 5-8 are well characterized with various spectroscopic methods and single-crystal X-ray structural analysis. This journal is © 2013 The Royal Society of Chemistry.

Petrenko V.Yu.,Institute of Semiconductor Physics of Ukraine | Dimitriev O.P.,Institute of Semiconductor Physics of Ukraine | Slominskii Yu.L.,Institute of Organic Chemistry NAS of Ukraine
Synthetic Metals | Year: 2015

Mutual influence of thiamonomethinecyanine dye and PEDOT:PSS in the dye-polymer composite solutions and films was studied. It was found that PSS tends to suppress formation of J-aggregates of the dye molecules in the solution, while there is a competition between sulfonic groups of dye and PSS for binding with the PEDOT backbone. Interaction of dye monomers with PEDOT:PSS at relatively small dye concentration in the composite film was found to suppress film conductivity, while dimerization of the dye molecules at higher concentration resumes conductivity of the composite film. Suppressed conductivity upon interaction of the dye and PEDOT backbone was explained by steric disparity of the distance between sulfonic groups of the dye molecule and the distance between positive sites of the planar PEDOT backbone which induces deformation of the latter. © 2015 Elsevier B.V. All rights reserved.

Davidenko N.,Taras Shevchenko National University | Davidenko I.,Taras Shevchenko National University | Ishchenko A.,Institute of Organic Chemistry NAS of Ukraine | Kulinich A.,Institute of Organic Chemistry NAS of Ukraine | And 3 more authors.
Applied Optics | Year: 2012

The principle of the photothermoplastic method of hologram recording and the general requirements for photothermoplastic holographic recording media based on photoconductive polymer films are considered. The holographic recording media obtained by the authors based on carbazolyl- and ferrocenyl-containing oligomers doped with respective squarillium or merocyanine dyes are discussed. Some examples of practical application of such media in holographic interferometry are demonstrated. © 2012 Optical Society of America.

Davidenko N.A.,Taras Shevchenko National University | Ishchenko A.A.,Taras Shevchenko National University | Ishchenko A.A.,Institute of Organic Chemistry NAS of Ukraine | Kulinich A.V.,Institute of Organic Chemistry NAS of Ukraine | Studzinsky S.L.,Taras Shevchenko National University
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2012

The absorption, fluorescence and fluorescence excitation spectra of polymer thin film composites based on poly-N-epoxypropylcarbazole (PEPC) doped with different content of anionic polymethine dye testify to the formation of contact ion-pair associates at high concentration of the latter. The photoconductivity of such composites in the visible spectrum region is observed, despite the absence in the polymer of any fragment capable of accepting a photoexcited electron from anionic dye chromophore. Analysis of the spectral data together with DFT/B3LYP quantum-chemical calculation of the HOMO and LUMO energies of the monomer N-methylcarbazole unit and the radical of the polymethine dye allowed us to suggest the possible mechanism of internal photoeffect in the investigated composites which is based on the formation of the contact ion-pair associates. © 2012 Elsevier B.V. All rights reserved.

Petrenko V.Y.,Institute of Semiconductor Physics of Ukraine | Dimitriev O.P.,Institute of Semiconductor Physics of Ukraine | Slominskii Y.L.,Institute of Organic Chemistry NAS of Ukraine | Smirnova A.L.,Institute of Organic Chemistry NAS of Ukraine
Chemical Physics Letters | Year: 2015

Excitation energy transfer between thiamonomethinecyanine dyes with similar chromophores and different end groups has been studied in composite solutions and films depending on the dye-dye molar ratio. Among monomers, dimers and J-aggregate forms of these dyes, only J-aggregates were found to contribute to the energy transfer process. It has been found that the efficiency of energy transfer between different J-aggregates reaches up to 40% in solutions and about 100% in films and such high efficiency was assigned to the large overlap of the emission and absorption bands of the dyes that play the role of the donor and acceptor, respectively. © 2014 Elsevier B.V. All rights reserved.

Discover hidden collaborations