The precipitation of nanosized crystals CuBr and CuCl in potassium aluminoborate glasses con taining additives of jointly introduced Cu and Br, as well as Cu and Cl, respectively, has been studied by the methods of small angle X ray scattering (SAXS) and X ray powder diffraction (XRPD) analysis. It has been found that, upon thermal treatments at temperatures close to the glass transition temperature T g , halide phases precipitate in the form of liquid drops containing CuBr and KBr or CuCl and KCl. The presence of nanocrystals CuBr or CuCl, respectively, has been established in the samples at room temperature by the XRPD method. Liquidus, solidus, and crystallization onset temperatures in the regions of precipitated halide phases in heat treated glass samples have been determined from the temperature dependences of SAXS inten sity. The liquid released upon the heat treatment inside a matrix of potassium aluminoborate glass remains in the state of a supercooled liquid at temperatures essentially below the solidus temperature. At the drop sizes of the order of 10 nm, crystallization processes in them start at temperatures of 40-85°C.

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The kinetics of the relaxation processes in silver iodide nanocrystals synthesized in a nanoporous silicate glass matrix and excited by femtosecond laser pulses has been experimentally studied. A short lived characteristic transmission band is found to be formed in the spectral range of exciton absorption of nanoc rystals. The specific features of photoexcited carrier relaxation, which are due to the energy redistribution of captured carriers over levels in the band gap of silver iodide nanocrystals, are considered. The energy transfer relaxation rates are estimated and possible mechanisms of the energy transfer are discussed.