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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.