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Spectral, luminescent, and lasing characteristics of chromene dyes and their julolidine analogs emitting in the red spectral range are investigated experimentally and theoretically. It is shown that the cause for a low lasing efficiency of oxochromene compared with iminochromene is a high intersystem crossing to the T 1 state and the presence of the induced T 1→T n absorption in the region of the luminescence band.

The results from investigating the photophysical properties of new coumarin dyes synthesized and incorporated into Langmuir-Blodgett films are presented. A method for forming monolayers on the surface of a water/air interface is proposed. The phase states of mixed monolayers on a water surface are studied. It is found that mixed monolayers of amphiphilic polyampholyte and dye allow us to obtain more stable and condensed films, relative to films of single components. The spectral and luminescent properties of synthesized dyes in solution and in Langmuir-Blodgett films are studied.

Spectral and luminescent properties were studied for chemical dimers and molecular aggregates of Nile Red oxazine dye in solutions. Chemical bonding of two oxazine dye molecules leads to the formation of a dimer whose spectral behavior is in close agreement with the exciton model constructed for “physical” molecular aggregates. Chemical dimers luminesce, whereas dimers formed because of van der Waals interactions do not.

A series of conjugates of sulfo- and carboxy-substituted phthalocyanines with rhodamines were prepared, and their electronic absorption and luminescence spectra were studied. An intramolecular transfer of the excitation energy from the rhodamine moiety (donor) to the phthalocyanine moiety (acceptor) was revealed.

Spectral-luminescent and lasing properties of new derivatives of Coumarin-7 were studied. Induced emission generation of studied dyes was observed in the red wave-length region of spectrum. The efficiency of lasing was equal to 40%. The threshold of generation of dyes was observed upon excitation with the power density less than 0.01 MW/cm2. It was revealed that studied dyes have a high photostability.

Nitro and amino derivatives of benzo[b]phenoxazine have been synthesized. The spectroluminescence properties of the synthesized compounds are investigated.

10-Hydroxy-5H-dibenzo(a,i)phenoxazin-5-one and its 6-chloro derivative - condensed derivatives of resorufin, simultaneously containing in the molecule linearly and angularly condensed benzene rings - were synthesized. Their spectral-luminescent properties were investigated.

We report the investigation findings of monolayers behaviour of nile red new synthesized amphiphilic analog at the air/water interface and its spectral-luminescent properties in solvents of various polarity and in Langmuir-Blodgett films consisting of dyes and stearic acid mixture. It is shown, that electronic absorption spectra of films depends on the presence of two monomer types of various spatial conformations. The position of the films fluorescence band is identical to a case of polar medium.

The synthesis of dibenzo[b,i]phenoxazine, its p-tert-butyl substituted analog, and a series of nitro-, amino-, and bromosubstituted derivatives, is described. The spectral luminescence properties of these newly synthesized compounds have been investigated.

We have recently studied the basic systematics of photolysis of oxazine dyes in alcohol solution under the action of continuous UV irradiation and have proposed that the accumulation of products which absorb in the lasing region is associated with photoreduction of the dye [I]. In the present work we have attempted to characterize quantitatively the dependence of the photoreduction efficiency upon the structure of tile dye and the wavelength of the exciting light. Our goal in this has been, on the one hand, to create a basis for forecasting the photostability of oxazine dyes and, on the other, to obtain additional information about the mechanism of photolysis.

Chloro- and alkoxy-substituted porphyrazines were obtained in the reaction of mono- and dichloromaleo (fumaro)nitriles with metal chlorides or alkoxides. The structures of the synthesized compounds were confirmed by their electronic absorption spectra.

Chloro- and alkoxy-substituted porphyrazines were obtained in the reaction of mono- and dichloromaleo (fumaro)nitriles with metal chlorides or alkoxides. The structures of the synthesized compounds were confirmed by their electronic absorption spectra.