@article{DimitrievGrytsenkoTolmachevetal.2014, author = {Dimitriev, O. P. and Grytsenko, Kostyantyn and Tolmachev, O. I. and Slominskii, Yu L. and Kudinova, M. A. and Schrader, Sigurd}, title = {Effect of Concentration on Isomerization of Rhodanine Derivatives of Merocyanine Dyes in Polar Solvents}, series = {Advances in Physical Chemistry}, volume = {2014}, journal = {Advances in Physical Chemistry}, issn = {1687-7993}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-5931}, pages = {9}, year = {2014}, abstract = {Rhodanine derivatives of merocyanine dyes with residues of 1,3,3-trimethyl-3H-indole and 3-ethylbenzothiazoline have been found to possess two molecular forms in diluted solutions of polar solvents such as dimethylformamide, dimethyl sulfoxide, and N-methylpyrrolidinone. The first molecular form was observed to prevail at low concentrations of the dyes, normally up to 10-5 M. The second one prevails at higher concentrations and is displayed through a new band in the electronic absorption spectrum, which is red-shifted with respect to the absorption band of the first form. No similar effect was found for these dyes by use of nonpolar solvents or upon alkyl-substitution of the molecules at nitrogen atom in the rhodanine moiety. We assign the above two forms to different molecular isomers and the analogous spectral changes were shown to take place by light or heat influence which correspond to a typical isomerization effect for the related merocyanine dyes. It is discussed that the isomer transformation is facilitated by the increased mobility of the proton bonded to the nitrogen atom of the rhodanine moiety in the polar environment and the increased amount of dye-dye collisions.}, language = {en} } @inproceedings{GrytsenkoDoroshenkoKolomzarovetal.2008, author = {Grytsenko, Kostyantyn and Doroshenko, T. and Kolomzarov, Yurii and Prokopets, Vadym M. and Fedoriak, O. and Zelinski, R. and Lytvyn, Oksana and Prescher, Dietrich and Grimm, Bernd and Ksianzou, Viachaslau and Schrader, Sigurd and Tolmachev, O. I. and Slominskii, Yu L. and Kurdiukov, V. and Smirnova, G.}, title = {Research on the growth of dye film in vacuum in situ}, publisher = {Society of Photo-Optical Instrumentation Engineers (SPIE)}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-15206}, pages = {318 -- 323}, year = {2008}, abstract = {Organic film deposition in vacuum is fast developing scientific and industrial domain. We developed installation for deposition of organic films equipped with optical spectrometer for measurements in situ. We are developing new dyes aimed for application in waveguide sensor, nonlinear optics and studying film organisation during deposition. Fluorinated azo-dyes and azomethine dyes were synthesized at University of Applied Sciences Wildau and at the Institute of Organic Chemistry, Kyiv. Compounds were evaporated at a pressure of 10-3 Pa using resistive heated crucible. Glass and glass covered with polytetrafluoroethylene (PTFE) film are used as substrates. The films were studied with Polytec and StellarNet spectrometers and an atomic force microscope. Optical spectra of the dye films revealed, that some compounds were decomposed during evaporation. Several kinds of dyes were evaporated and deposited without decomposition. Some deposited films formed H-aggregates and other types of aggregates. AFM images of dye films showed that their morphology depends on the chemical structure of the compounds and on the nature of the substrate on which the film was grown.}, language = {en} } @inproceedings{GrytsenkoSlominskiiTolmachevetal.2008, author = {Grytsenko, Kostyantyn and Slominskii, Yu L. and Tolmachev, O. I. and Resel, R. and Ksensov, S. and Schrader, Sigurd}, title = {Enigma of the second harmonic generation in oriented film of symmetric squaraine}, publisher = {Society of Photo-Optical Instrumentation Engineers (SPIE)}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-15183}, pages = {324 -- 331}, year = {2008}, abstract = {Second harmonic generation (SHG) in the oriented film of symmetric squaraine (Sq) was studied. Oriented Sq film on aligned polytetrafluoroethylyne (PTFE) sublayer prepared by vacuum deposition with subsequent rubbing using a cloth has been obtained. However, the mechanisms of orientation and SHG are still not clear. Methyl and ethyl substituted hydroxyl-Sq (OHSq) compounds formed oriented films with dichroic ratio of 8 on PTFE layer but with dichroic ratio of 1,5 on Teflon AF. Second layer deposition of Me-OHSq on Et-OHSq or of Et-OHSq on Me-OHSq led to an increase of the film dichroic ratio. Only the film, where Me-OHSq was first layer, exhibits an increase of SHG signal after deposition of second layer. Small differences in bi-layered OHSq films structure was detected by X-Ray diffraction (XRD) spectra.}, language = {en} }