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The problem of identifying correlations between catalytic and electrocatalytic processes is one of the fundamental problems of catalysis among “simple” organic substances, and the oxidation of CO and rCO2 is of great interest, since CO and CO2 are considered in pairs both during catalytic and electrocatalytic transformations. In the case of electrocatalysis, this analysis is important in the study of fuel cells. In this paper, we studied the correlation between the oxidation of reduced forms of CO2 (rCO2) under potentiodynamic-galvanoctatic electrochemical and open-circuit conditions of measurements on polycrystalline (pc)Pt in H2CO3. Periodic oscillations are revealed at the oxidation of Had and rCO2 on (pc)Pt. Quantum chemical calculations were carried out on the Pt13 cluster in order to identify the mechanisms of the rCO2 oxidation reaction. The correspondence in the energy parameters of the oxidation process of rCO2 under open-circuit conditions and electrochemical conditions is shown. The preliminary analysis of the system using density functional (DFT) calculations is carried out and the most stable systems that are based on Pt13 are found, namely rOH-Pt13-(CO)n, rOH-Pt13-(COH) and rOH-Pt13-(rCOOH). OH• species was chosen as the most likely candidate for the role of the oxidant for rCO2. Preliminary calculations for the expected reactions were carried out, and the optimal PES is revealed.

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The article discusses the results of study for the optical properties (luminescence) of aqueous solutions with low concentrations of lucigenin. One new methodology for the mathematical processing of luminescence spectra is presented. The method to prepare the solutions, which can be used to identify critical points (D.I. Mendeleev's decrement) in the physicochemical properties of aqueous solutions, is considered.

An approach has been proposed for determining the space-time parameters of the formation pro cess of Liesegang rings. This approach relates the processes of the formation of nanoparticles and dense peri odic precipitates from them. Dynamic light scattering is employed to reveal periodic variations in the inten sity of light scattered by nanoparticles with different sizes, from which Liesegang rings are formed. A relation ship between the periods of the variations in the intensity of light scattered by nanoparticles (microscopic process) and the times of the formation of Liesegang rings as a whole (macroscopic process) has been found.