E. N. Nikonova

Computational and experimental investigation of the optical properties of the chromene dyes.

Absorption and fluorescence spectra of the chromene 3 and chromene 13 dyes are studied experimentally and by density functional theory (DFT) including vibronic structure analysis. Vertical electronic absorption spectra are also calculated with the ab initio multiconfiguration method XMC-QDTP2. The vibronic progression for the S0 → S1 electronic transition is calculated within the Franck-Condon approximation including Dushinsky effect and promoting modes are analyzed. The laser-active solid-state media with high efficiency and long operation time are created implementing the studied dyes. The results of investigation indicate that the studied compounds can be used as effective laser dyes in the red range of visible light.

Optical and electroluminescent properties of a number of new derivatives of divinyl dibenzothiophene sulfone

Photoluminescent and electroluminescent properties of four new bipolar linear derivatives of divinyl dibenzothiophene sulfone are studied. It is found that amorphous films of solutions, as well as films of the compounds under study in the poly(N-vinylcarbazole) matrix, have a rather high quantum yield of photoluminescence in the blue and blue-green spectrum regions. Bright blue electroluminescence is obtained in the samples with a structure of ITO/PEDOT:PSS/TPD/OC/LiF/Al using vacuum deposition of the compounds under study and in the single-layer ITO/PEDOT:PSS/PVK:OC/LiF/Al structure when applied from the solution with a threshold voltage of 2.5–3.5 V. The influence of a molecule structure on the spectra and quantum yield of fluorescence as well as on the electroluminescent properties of the compounds is shown. Results of quantum-chemical calculations in the context of the density functional theory of the structure and characteristics of main molecular orbitals are presented.