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¹H NMR spectroscopy of adsorbed water was used to study mesoporous silica gel and carbosils synthesized with carbon in the range from 4 to 14.5% w/w in the surface layer. It has been revealed that both silica gel and carbosil are characterized by a rise in temperature of water freezing in an aqueous medium in mesopores. This phenomenon may be explained by contact of water adsorbed in pores with a continuous aqueous medium. The changes in free energy of water in pores due to adsorption have been calculated. It has been shown that carbonization of the mesopore silica gel surface leads to formation of carbon layers which are denser than those on a nonporous silica and the main types of water adsorption sites on the surface are basic graphite planes of carbon and oxygen-containing groups on the carbon part of the carbosil surface.

The application of several physicochemical parameters of organic compound structures for description of their nonspecific and specific interactions at adsorption on the oxide surface as well as for chemisorption kinetics in these systems is discussed. An approach to calculate the distribution functions on the coefficients of linear equations, connecting the adsorption or chemisorption parameters on the heterogeneous surface with physicochemical parameters of adsorbates or reagents, is presented. It has been used for the description of some adsorption equilibria and chemisorption kinetics of organosilicon compounds on the SiO2 surfaces and for determination of the dispersive and specific components of the free surface energy of Si, Ti, and Al oxides.

The MINDO/3 method was used to study the effect of intensity and vector direction of the external electric field on activation barriers of unimolecular reactions which are possible in electrochemical transformations of simple organic compounds:  orientation of molecules and radical anions, heterogeneous electron transfer to adsorbed molecules, dissociation of radical anions, cations, and molecules, inversion of anions, free radicals, and neutral molecules, cis−trans isomerization, and chair−boat conformational transition in molecules. The electronic and spatial structure of the molecules, free radicals, and ions, the height of the activation barriers of their reorientation, dissociation, isomerization, and conformational transition, and the configurational stability to change as affected by the field in the range 0.01−0.05 au are determined. Obtained data permit one to theoretically ground different effects under organic compound adsorption on the electrode surface, changes in stereochemistry of the products of alkyl halide electroreduction, and some properties of chemically modified electrodes possibly affected by electrode potential gradient.

Quantum chemical computations of potential energy surface sections along the reaction pathway for interaction of some molecules with silica surface OH groups in a cluster approach have been performed. Two minimums on the potential curves which are due to formation of linear hydrogen-bonded and following cyclic donor−acceptor complexes were observed prior to formation of the transition state for proton transfer in the cyclic complexes. Some tendencies between quantum chemical indexes of organic molecules and heats of the complex formation or chemisorption activation energies on the silica surface have been established.