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www.rsc.org/ ab Ruthenium(II) tetra-15-crown-5-phthalocyaninate with axially coordinated molecules of pyrazine [(15C5)4Pc]Ru (pyz)2 (1) was synthesized from carbonyl complex [(15C5)4Pc]Ru(CO)(MeOH) (2),and the structure of the solvate complex (1)·6CHCl3 was revealed by the single crystal X-ray diffraction method. Analysis of crystal packing shows the essential role of weak intermolecular interactions, such as CH…π, CH…N, CH…O and CH…Cl, in the formation of stable assemblies and their organization within the crystals. The interplay between the intramolecular axial coordinated pyrazine contacts and weak intermolecular interactions of solvate molecules with crown-ether fragments provides the basis for rationalizing the observed self-assembling of molecules in solutions of tetrachloroethane and polymeric composites with polyvinylcarbazole. The self-assembling was investigated by means of UV-Vis spectroscopy, dynamic light scattering measurements, AFM and TEM techniques. The formation of nanoparticles of complex (1) from a tetrachloroethane solution after three cycles of heating to 70°C/cooling to 5°C and 2-days storage was proved. Thin films (7 µm) of polymeric composites with polyvinylcarbazole prepared from solution containing nanoparticles exhibit nonlinear optical response measured by the Z-scan technique with application of femtosecond (1030 nm) and nanosecond (1064 nm) pulse lasers.The measured third-order susceptibility (χ (3) ) of the polyvinylcarbazole composite with 4 wt% of complex (1) is equal to 1.94×10 -10 esu, while the same composite prepared without the above-described special treatment has zero susceptibility.This result proves the essential role of self-assembling in further development of nonlinear optical materials.

Metal-organic frameworks (MOFs) demonstrate unique properties, which are prospective for drug delivery, catalysis, and gas separation, but their biomedical applications might be limited due to their obscure interactions with the environment and humans. It is important to understand their toxic effect on nature before their wide practical application. In this study, HKUST-1 nanoparticles (Cu-nanoMOF, Cu3(btc)2, btc = benzene-1,3,5-tricarboxylate) were synthesized by the microwave (MW)-assisted ionothermal method and characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) techniques. The embryotoxicity and acute toxicity of HKUST-1 towards embryos and adult zebrafish were investigated. To gain a better understanding of the effects of Cu-MOF particles towards Danio rerio (D. rerio) embryos were exposed to HKUST-1 nanoparticles (NPs) and Cu2+ ions (CuSO4). Cu2+ ions showed a higher toxic effect towards fish compared with Cu-MOF NPs for D. rerio. Both forms of fish were sensitive to the presence of HKUST-1 NPs. Estimated LC50 values were 2.132 mg/L and 1.500 mg/L for zebrafish embryos and adults, respectively. During 96 h of exposure, the release of copper ions in a stock solution and accumulation of copper after 96 h were measured in the internal organs of adult fishes. Uptake examination of the major internal organs did not show any concentration dependency. An increase in the number of copper ions in the test medium was found on the first day of exposure. Toxicity was largely restricted to copper release from HKUST-1 nanomaterials structure into solution.

The shift of the localized surface plasmon resonance (LSPR) band of gold nanoparticles to shorter wavelengths upon saturation of the hydrosol with hydrogen is used as a tool to study the electrochemical processes on the particle surface. It is shown that dissociative adsorption of hydrogen takes place on the surface of a particle and results in the migration of a proton into the dispersion medium, while the electron remains on the nanoparticle, i.e., a hydrogen-like nanoelectrode is formed. It is shown that Au(iii) ions can be reduced on the gold nanoelectrodes. A thermodynamic scheme explaining the shift of the LSPR band is used to explain the peculiarities of the Au(iii) ion reduction. The reduction rate does not depend on the ion concentration and varies linearly with pH. The observed correlations are explained in terms of a simple model of electrochemical processes taking place on the nanoparticle as an electrode. It is shown that with an increase in the particle size, its capacity for dissociative adsorption of hydrogen decreases and the Au(iii) reduction slows down.