Isothermal vapor−liquid equilibrium (VLE) for thiophene + n-hexane at (338.15 and 323.15) K and thiophene + 1-hexene at (333.15 and 323.15) K were measured with a circulation still. Maximum pressure azeotropes were found in the thiophene + n-hexane system. Azeotropic behavior was not found for the thiophene + 1-hexene system. The experimental results were correlated with Wilson model and also compared with original UNIFAC, UNIFAC−Dortmund, and COSMO-RS predictive models. Analyses of liquid and vapor-phase composition were determined with gas chromatograph and refractometer. All VLE measurements passed the three thermodynamic consistency tests used.

Redox-isomerism, i.e. the change of metal cation valence state in organic complexes, can find promising applications in multistable molecular switches for various 2 molecular electronic devices. However, despite a large amount of studies devoted to such processes in organic complexes of multivalent lanthanides, redox-isomeric transformations were never observed for europium. In the present work, we demonstrate the unique case of redox isomerization of Eu(III)/Eu(II) complexes on the example of Eu(III) doubledecker octa-nbutoxyphthalocyaninate (Eu[(BuO)8Pc]2) under ambient conditions (air, room temperature). It is shown that assumption of the face-on orientation on the aqueous subphase surface, in which two of each phthalocyanine decks in Eu[(BuO)8Pc]2 are located in different media (air and water), leads to the intramolecular electron transfer that results in formation of divalent Eu(II) cation in the complex. Lateral compression of the thus formed monolayer brings on the reorientation of the bisphthalocyaninate to the edge-on state, in which the ligands can be considered identical, and occurrence of the reverse redox-isomeric transformation into the complex with trivalent Eu cation. Both redox-isomeric states were directly observed by XANES spectroscopy in ultrathin films formed under different conditions.

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Nanocrystalline ZnO, ZnO(Ga), and ZnO(Ga, In) samples with different indium contents were prepared by wet-chemical method and characterized in detail by ICP-MS and XRD methods. Gas sensing properties toward NO 2 were studied at 150-450 • C by DC conductance measurements. The optimal temperature for gas sensing experiments was determined. The dependence of the ZnO(Ga, In) sensor signal to NO 2 at 250 • C correlates with the change of conductivity of the samples. The introduction of indium into the system leads to an increase in the values of the sensor signal in the temperature range T < 250 • C. The investigation of the local sample conductivity by scanning spreading resistance microscopy demonstrates that, at high indium content, the sensor properties are determined by the In-Ga-Zn-O layer that forms on the ZnO surface.

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