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To study the effect of volume and surface defects on the thermodynamic and structural characteristics of nanoclusters of cobalt and copper, the Monte Carlo method was applied. The interaction between atoms was described by the many-body Gupta potential. It is determined that in simulation of thermal exposed metallic nanoparticles with point defects there are insignificant deviations of their structural characteristics from values corresponding to non-defect nanoparticles.

Shungites have been studied by high-resolution transmission electron microscopy (HRTEM). Two types of carbon layers have been revealed in shungites by HRTEM. The first type, graphite-like carbon layers are characterized by strongly marked hexagonal symmetry. The second type are remarkable for imperfections connected with insignificant disorder in the direction of fringes and the distance between them, and can result from point defects or the pentagonal and heptagonal carbon rings that are signs of fullerene-like structures.

Ab-intio study of the interaction of atomic and molecular oxygen with the TiNi(1 1 0) surface was performed using the projector augmented wave method with generalized gradient approximation for the exchange-correlation functional. The oxygen adsorption energies were calculated and the preferential adsorption sites of oxygen atom on the surface were determined. Our results confirmed the formation of a Ni-rich layer at the alloy–oxide interface. Atomic and electronic structure of both TiO/TiNi(1 1 0) and TiO2/TiNi(1 1 0) interfaces were analyzed. The formation energies (Ef) of point defects at the interfacial layers as well as in bulk TiNi, monoclinic TiO, and rutile TiO2 were estimated. It was shown that Ef of Ti–Ni swap defect has a lower energy than that for the Ni antisites at the TiO2(1 0 0)/TiNi(1 1 0) interface. In the case of TiO(1 0 0)/TiNi(1 1 0) interface, the formation energies of Ti–Ni swap and Ni-antisites defects are close to each other. Our results demonstrated that Ef of Ni-defect in TiO is twice less than that in TiO2. The increase in the formation energies of defects in TiO2 reveal the increase in diffusion barriers of Ni atoms in comparison with those in oxides with a lower oxygen content, which hampers Ni segregation.