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Multilayer films of two types, namely, films with alternating nanolayers Ag 2 S and AgI and alternating nanolayers Ag 3 SI and AgI, are prepared by laser ablation. The conductivity of the film samples is investigated using impedance spectroscopy. The ends of fractures of the multilayer films are examined with electron microscopy.

Solid solutions Rb 0.95 Nb x Mo 2−x O 6.475−0.5x (x = 1.31−1.625) having a β-pyrochlore structure with an orthorhombic system were synthesized by solid-state reaction. The elemental composition was confirmed by X-ray microanalysis. The Rb 0.95 Nb 1.375 Mo 0.625 O 5.79 structure refinement was performed using the Rietveld method. The crystal structure consists of ordered O−Mo−O chains partly occupied by Nb atoms. The oxygen vacancies are necessary to save the electroneutrality of the unit cell. It predominantly appears between Mo atoms that lead to form two disconnected defect octahedra [MoO 5 □•••MoO 5 □].The structural defects cause the low thermal stability; the compounds obtained decompose in the 748−758 °C temperature range. The high-temperature phase transition of the CsNbMoO 6 and CsTaMoO 6 nonlinear optical β-pyrochlores has been studied by differential thermal analysis, differential scanning calorimetric analysis, high-temperature X-ray diffraction analysis, and second harmonic generation analysis. At room temperature the compounds possess the cubic noncentrosymmetric F4̅ 3m cell. Under heating to 437 °C and 401 °C for CsNbMoO 6 and CsTaMoO 6 , respectively, they undergo transition into centrosymmetric Fd3̅ m modification. This is accompanied by the SHG signal disappearing, as well as the 402 reflection, which is characteristic of the F4̅ 3m space group. The positions of the valence and conduction bands were determined by reflectance spectra and XPS analysis for structure-related β-pyrochlores CsNbMoO 6 , CsTaMoO 6 , and Rb 0.95 Nb 1.375 Mo 0.625 O 5.79 .

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New organic–inorganic hybrids have been synthesized by the intercalation of n-alkylamines (methylamine, ethylamine, n-propylamine, n-butylamine, n-hexylamine, and n-octylamine) into the structure of the protonated and hydrated form of the perovskite-like layered titanate H2K0.5Bi2.5Ti4O13·H2O (HKBT4·H2O). The possibility of the synthesis of the hybrid materials was studied in a wide range of conditions. It was found that interlayer water plays a crucial role in the formation of intercalated hybrids. The obtained compounds were characterized with powder X-ray diffraction analysis; Raman, IR, and NMR spectroscopies; thermogravimetry (TG), TG coupled with mass spectrometry, and CHN analyses; and scanning electron microscopy. It was suggested that the intercalated n-alkylamines exist in the form of alkylammonium ions forming a paraffin-like bilayer with an average tilting angle of ∼77.5°. The obtained HKBT4×RNH2 compounds contain 0.4–0.7 n-alkylamine molecules per formula unit as well as the varied amount of intercalated water. By gentle heating, they can be obtained as dehydrated forms, which are thermally stable up to 250 °C.

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