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The reaction of cadmium, manganese, and lead trifl uoroacetates with thioacetamide in methyl methacrylate yielded colloidal solutions of metal sulfi des with different Cd(II) : Mn(II) : Pb(II) molar ratios. The colloidal particles were separated from solutions and examined by electron microscopy. Glassy polymer composites poly(methyl methacrylate):Cd(Mn)S and poly(methyl methacrylate):Cd(Mn,Pb)S were prepared by thermal polymerization of methyl methacrylate in the bulk. The transmittance of the composites at wavelengths larger than 480 nm is 92% at the sample thickness of 0.40 cm. The luminescence of the composites in the visible range is associated with cadmium sulfi de. The corresponding absorption bands were recorded in the luminescence excitation spectra in the wavelength interval 300-450 nm. The effect of the matrix, Mn(II) and Pb(II) ions, and synthesis conditions on the absorption and luminescence properties of the composites was determined.

The technique of synthesis of polymethylmethacrylate -cadmium sulfide nanocomposites involving precipitation of CdS nanoparticles from polymethylmethacrylate solution in methylmethacrylate monomer with its subsequent polymerization is presented. The influence of molecular polymer mass and polymerization conditions on the dispersion stability is discussed. The spectral-luminescent properties of nanocomposites are investigated. A difference between the spectral-luminescent properties of the surface composite layer and the nanomaterial bulk, connected with redistribution of particles with higher degree of imperfection closer to the surface during polymerization is revealed.

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We study the dynamics of multi-level quantum systems under the influence of electromagnetic field. Basing on the path integral approach to the quantum density matrix and transitions probability we represent functional averaging electromagnetic field influence. We demonstrate that the transition probability can be written as a path integral of real functional (the product of exponent and cosine). The numerical integration algorithm of the transitions probability in energy representation was developed. The numerical simulations of the quantum system dynamics under electromagnetic field action describe the well-known Rabi oscillations, their fluctuations and multi-photon quantum transitions.