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The dynamics of a C60 fullerene located near the axis of rotation of a fullerite fragment of consisting of 63 fullerenes forming a face-centered cubic lattice has been studied numerically. The achiral molecule C60 under consideration has the highest symmetry in the fullerene family and is mathematically modeled as a discrete covalent molecule or as a spherical particle. This molecule rotates around its center of mass in a fullerite crystal with a frequency of about 100 GHz. Numerical study of C60 molecular rotators located in rotating reference frames was carried out using molecular dynamics methods, a hybrid discrete–continuous mathematical model, the Euler approach and the fourth order Runge–Kutta method for numerical solution of differential equations. A parametric study of the influence of the direction and frequency of rotation of a molecular cluster (up to 1 GHz) on the reorientation time and rotational dynamics of the fullerene molecule was carried out in the picosecond range (up to 10 ps). Chiral phenomena in the C60 molecular crystal and the logarithmic dependence of the reorientation time of C60 fullerene on the rotation period of the fullerite were discovered based on the results of numerical calculations. [ABSTRACT FROM AUTHOR]

Molecular dynamics is applied to study the effect of crystallographic orientation on the plastic deformation mechanisms and mechanical properties of NiAl intermetallic nanofilms subjected to uniaxial tension. It is observed that the deformation mechanisms qualitatively depend on the crystallographic orientation of the nanofilms with respect to the loading direction. Plastic deformation of the nanofilms along [557] crystallographic direction is associated with the edge dislocation sliding in the slip system [001](110). As for the nanofilms stretched along [554] and [111] directions, their deformation occurs first through the dislocation sliding followed by the formation of (112)[11 1] twins. Uniaxial tension of the nanofilms along [559] and [55 11] leads to the nucleation and growth of a martensitic phase followed by their rupture along an interface. The maximum (minimum) strength of 9.9 (7.0) GPa is observed for the nanofilms stretched along the [559] ([554]) crystallographic direction, while the largest (smallest) strain to failure of 27 (15)% is for [559] ([55 11]). Various deformation mechanisms of the nanofilms are explained through computing the Schmid factor for the operational slip system. The results indicate that the crystallographic orientation is among the key parameters controlling the deformation mechanisms and mechanical properties of intermetallic nanofilms.

Columnar phases consisting of a group of carbon toroidal molecules (C120, C192, C252, C288) are studied numerically. Each nanotorus was previously doped with an iron atom. This made it possible to use an external magnetic field as a tool for influencing both an individual molecule and a linear fragment of the columnar phase. A high-precision scheme for calculating the dynamics of large molecules with a rigid frame structure is proposed to solve the problem. The group dynamics of nanotori clusters under the influence of an external magnetic field has been studied using classical molecular dynamics methods. The influence of the molecular cluster size, temperature, magnetic moment of the molecule, and magnetic field direction on the collective behavior of iron-doped toroidal molecules with different contents of carbon atoms is analyzed. Molecular dynamics calculations showed that systems of nanotori doped with a single iron atom retain a columnar structure both in the absence and in the presence of an external magnetic field. The columnar fragment behaves as a stable linear association of molecules even at sufficiently high values of magnetic induction, performing a coordinated collective orbital rotation around a common center of mass on a nanosecond time scale. [ABSTRACT FROM AUTHOR]

Using the example of C59Fe, the paper describes a scheme for calculating the motion of a magneto-susceptible molecular object in an alternating magnetic field. Two modes of angular displacements of the molecular structure under consideration are determined by calculation. The possibility of forming the spin of the molecule is shown. [ABSTRACT FROM AUTHOR]

The molecular dynamics of the interaction of a carbon nanotorus with a C60 fullerene have been calculated. The trajectories of the centers of mass of individual molecules have been calculated together with the frequencies of their rotations and accordingly, the trajectories of each atom. The temperature of the system has also been studied. An unstable rotation mode of the C60–nanotorus system was found and analyzed in the Louis Poinsot plane. The locus of points in the nanotorus is found with the highest probability of finding the fullerene center of mass due to the potential well of the carbon nanotorus. [ABSTRACT FROM AUTHOR]

The radiation intensity of the outer shell of a carbon onion complex containing an ionized iron atom is calculated according to the scheme proposed by L. D. Landau. A complete description of the oscillations arising in the system under consideration is given. [ABSTRACT FROM AUTHOR]

We consider a layer of open nanotubes identically oriented in space. We investigate permeability of a nanoporous carbon system for a regular triangular packing of tubes. Curves defining layer permeability depending on the degree of spatial proximity of tubes are constructed.

The results of numerical modeling of the process of free convective heat transfer in the regime of turbulent convection in a closed rectangular region heated by an infrared radiator are presented. The system of Navier-Stokes equations in the Boussinesq approximation is solved, the energy equation for the gas and the heat conduction equations for the enclosing vertical and horizontal walls. A comparative analysis of the heat transfer regimes in the considered region for different Grashof numbers is carried out. The features of the formation of heated air flows relative to the infrared emitter located at some distance from the upper horizontal boundary of the region are singled out.