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The nature of the hydrogen bond is investigated by means of a comparative analysis of some hydrogen bonded and hydrogen-like bonded systems. It is concluded that the hydrogen bond is determined by electrostatic interaction between the proton and the region of high electron density in the neighbour molecule.

The studies concerned with the oxidation of carbon monoxide on the nickel surface are reviewed. The Eley-Rideal (ER) collision and Langmuir-Hinshelwood (LH) The oxidation of carbon monoxide with metal catalysts was studied by many authors [1][2][3][4]. However, there are numerous discrepancies between their results, which concern both the reaction mechanism and basic kinetic characteristics [2, 4]. In [5, 6] it is shown that during the oxidation of CO at low pressures, oxygen is irreversibly adsorbed on Pt or Pd by dissociation, and the gas-phase CO molecules react with the atomic oxygen adsorbed on the surface. This oxidation path is referred to as the Eley-Rideal (ER) collision mechanism [4]. The reality of the collision mechanism has been the subject of debate. This problem is of fundamental importance for explanation and prediction of catalytic effects. Validity of the collision mechanism means that the chemisorbed oxygen is reactive enough to interact with the oxidized substance without catalytic activation. In this case, the role of catalyst is determined only by its effect on oxygen, i.e., by the bond energies and reactivity of oxygen atoms on the surface. Unlikeliness of the collision mechanism of the reaction means that both oxygen and the oxidized substance should be catalyzed. In this case, CO can chemically interact with the catalyst to yield an activated complex involving the catalyst together with chemisorbed O and CO, i.e., the reaction follows the Langmuir-Hinshelwood (LH) adsorption mechanism [4].In [7], it was established that in the oxidation of CO on a polycrystalline plate by the LH adsorption mechanism the activation energy is 92 kJ/mole, and the interaction between oxygen and gas-phase or weakly bound CO by the ER collision mechanism occurs with zero activation energy. The activation effect of palladium catalysts on the oxidation of CO is similar to that of platinum catalysts. In the most comprehensive studies of the oxidation of CO on palladium Kiev Polytechnical Institute.

The SCF MO LCAO method in the valence approach with neglect of diatomic differential overlap (NDDO) is used to study the effect of atomic hydrogen on the silicon lattice relaxation in the nearest vicinity of a vacancy. It is shown that hydrogen atoms are localized mainly as second-nearest neighbours of the vacancies on the Si - Si bond, which results in a significant extension of the vacancy region. The potential barrier height and its dependence on the vacancy charge state were calculated for Frenkel pair annihilation with a hydrogenated vacancy in the cases of hydrogen localization inside and outside the vacancy. The results substantiate a model of enhanced annihilation of Frenkel pairs in hydrogenated crystalline Si.

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