In accordance with the orientation ratio (110), [001]β || (111), [$$1\bar {1}0$$]α established by fast electron diffraction between the ordered (β) and disordered (α) phases in the foil of a Pd + 57 at % Cu solid solution, the atomic structure of the interface is modeled by molecular dynamics. It is found that the structural and size discrepancies are compensated by interfacial dislocations with Burgers vectors a/2〈111〉 in coordinates of the β-phase.

Influence of oxygen on silicon nanocrystals formation peculiarities and size in semi-insulating polycrystalline silicon thin films has been demonstrated by the means of local atomic surrounding sensitive electronic structure experimental studies. Low-pressure chemical deposition from the gas phase at a relatively low temperature leads to formation of semi-insulating polycrystalline silicon film containing nanocrystals with the grain size of 20-40 nm. At the same time, films oxygen doping result in formation of silicon nanocrystals arrays with the mean particle size less than 10 nm. Possibility of size-controlled Si nanocrystals formation followed by electronic structure reconstruction of amorphous films with nanocrystalline inclusions is discussed and can be found prospective for a range of possible applications.

In accordance with the orientation relation (110),<001>β || (111),<110> α, established by the fast electron diffraction method between ordered (β) and disordered (α) phases in the Pd – 57 at .% Cu solid solution foil , the atomic structure of the interface is modeled by molecular dynamics. It is found that the structural and dimensional mismatch is compensated by interfacial dislocations with Burgers vectors a / 2 <111> in β-phase coordinates.

The β $$ \rightleftarrows $$ α phase transformations in foil of the Pd–52 at % Cu solid solution prepared by rolling have been studied using X-ray diffractometry and resistivity measurements during thermal heating–cooling cycles or lamp processing (LP) using light from high-power pulsed xenon lamps, followed by cooling. The results demonstrate that complete ordering of the two-phase (α + β) as-prepared (as-rolled) foil follows the sequence (α + β) → β → α → β in the first heating–cooling cycle and β → α → β in the second and subsequent cycles. When a radiative energy critical for a given thickness of foil with an ordered structure is delivered to the foil surface, an irreversible β → α phase transformation occurs, whose rate can be three orders of magnitude higher than the rate characteristic of the disordering process during Joule heating. After LP, the reversibility of the β $$ \rightleftarrows $$ α phase transformations, inherent in the initial, ordered structure, is observed in a second thermal cycle: heating to 700°C and cooling. The sequence of phase transitions is α → β → α → β in the first cycle and β → α → β in the second and subsequent cycles. The localization of light in the skin layer and finite thermal conductivity offer the possibility of producing a structure with a phase composition gradient at subcritical irradiation times. The fact that the LP-stabilized α-phase persists up to 300°C makes it possible to compare the mechanical properties of foil samples having identical elemental compositions but different (ordered and disordered) structures.

В настоящей работе предложена новая методика построения решетки совпадающих узлов для ОЦК и ГЦК кристаллов. Получены условия образования орторомбической, тетрагональной и кубической решетки совпадений и указаны конкретные решетки этих сингоний. Показаны возможные поликристаллические структуры, имеющие общую решетку совпадающих узлов.

Hydrogen diffusion in palladium bicrystals containing a small-angle twist or tilt boundary or a large-angle boundary similar to a special boundary is investigated using molecular dynamics simulation. We assess the effect of grain boundaries on the hydrogen diffusion process. The types of grain boundaries considered here are shown to differ in their absorption activity for hydrogen. The temporal grain-boundary segregation of hydrogen atoms can be accounted for in terms of their coordination, which differs significantly from that in the grain bulk.

The present review details the results of studies that showcase the capacity of the molecular dynamics method to analyze the atomic structure of small-sized metallic objects: nanoparticles, thin films, and film heterostructures.

The specific features of the heteroepitaxial growth of Cu-Pd solid solution films on the (001) surface of a Pd crystal at temperatures of 600 and 1000 K have been investigated using the molecular dynamics simulation. The condensation from a two-component flow has been simulated by a sequential deposition of Cu and Pd atoms with concentrations of 60 at % Cu and 40 at % Pd by portions of 0.1 ML, which corresponds to an effective deposition rate of ∼3.3 × 109 ML/s. It has been established that there is a coherent conjugation of the crystal lattices of the film and the substrate. The growth is accompanied by the formation of an intermediate solid solution monolayer phase: the phase is formed in the first layer of the film at a temperature of 600 K and in the upper layer of the substrate at 1000 K.

Hydroxyapatite Ca10(PO4)6(OH)2 (HA), space group of symmetry Р63/m, is a key calcium phosphate employed for the manufacture of biologically active ceramic materials for medical purposes used to recon� struct bone tissue defects [1]. Therefore, the views on the intragrain substructure, the structure of internal

The structure of the (001) fcc/(001) fcc interphase boundary of a system consisting of a hemispherical Ni (or Cu) crystal nanoparticle and a Pd crystal substrate was studied depending on the nanoparticle rotation angle θ = 15°, 20°, 25°, and 30°. A molecular dynamics simulation including multiparticle potentials calculated in the framework of the embedded atom method was used in this study. It was shown that, under given annealing conditions, the nanoparticle rotation depends on the size; namely, the annealing of small nanoparticles leads to their rotation to the position corresponding to the coincidence orientation at the interphase boundary, while the position of large islands remains practically unchanged. It was established that the atomic rearrangement at the interphase boundary affects only lattices with a larger parameter.