https://www.elibrary.ru/title_about_new.asp?i
1605-8119
Materials physics and mechanics
9
1
2010
1-83
RAR
RUS
1-10
Sanin
Peter the Great St. Petersburg Polytechnic University
St.Petersburg, Russia
Bagmanov
Quantum Oscillator under External Impulse Force
In this contribution dynamics of quantum oscillator under external impulse force is investigated. The oscillator with symmetric polynomial potential in the well of impenetrable walls is considered. The potential consists of quadratic and cubic terms; the cubic term depends on modulus of coordinate. Influence of walls and anharmonicity on vibrations is discussed. Properties and peculiarities of resonances have been studied in context of non-stationary Schrödinger's equation at specified initial conditions. Solutions for the probability density, expectation coordinate as function of time; Fourier's spectra were analyzed in detail.
Quantum Oscillator
External Impulse Force
https://mpm.spbstu.ru/article/2010.12.1/
MPM_9_1_P01.pdf
RAR
RUS
11-19
Melker
A.I.
Peter the Great St. Petersburg Polytechnic University
St.Petersburg, Russia
Krupina
Peter the Great St. Petersburg Polytechnic University
St.Petersburg, Russia
Hidden Symmetry or why Ciclic Molecules Have so Strange Forms
In this contribution we report on a study of conformation transitions in a cyclohexane in the temperature range from –100° to 1200°С. The bond charge molecular dynamics was used. To explain the results obtained, we have developed a method with the help of which the theory of electron pairs repulsion can be enlarged and be applied to cyclic molecules. The approach created reveals a hidden symmetry of spatial electronic structure which, in general, does not coincide with the symmetry of a visible atomic structure. However this spatial electronic structure presets an atomic structure and explains why a cyclohexane molecule has so unusual conformations as a boat and a chair.
Ciclic Molecules
Hidden Symmetry
https://mpm.spbstu.ru/article/2010.12.2/
MPM_9_1_P02.pdf
RAR
RUS
20-25
Krupina
Peter the Great St. Petersburg Polytechnic University
St.Petersburg, Russia
Melker
A.I.
Peter the Great St. Petersburg Polytechnic University
St.Petersburg, Russia
Unified Approach to Vibrations and Rotations of Molecules and Macromolecules
In this contribution we have briefly analyzed the approach lying at the basis of semi-empirical calculation of the potential barrier for molecule internal rotations. In opposite to it, we have suggested the way how to find this barrier on purely theoretical grounds. For this purpose, we have used the bond-charge model with clamped charges, and in this contribution restricted ourselves by the simplest case of such molecules as ethane. It was found that this approach leads to theoretical results which are in a good agreement with experimental data. It means that the electronic theory of molecule vibrations developed earlier has a large degree of generality and can be used to study not only vibrations but also rotations of molecules and macromolecules on the basis of one and the same approach, excluding a lot of empirical parameters which are often do not clarify a subject but immerse it into darkness.
Molecules
Macromolecules
Vibrations
Rotations
https://mpm.spbstu.ru/article/2010.12.3/
MPM_9_1_P03.pdf
RAR
RUS
26-34
Nelayev
Belarusian State University of Informatics and Radioelectronics
Minsk, Belarus
Mironchik
Belarusian State University of Informatics and Radioelectronics
Minsk, Belarus
Magnetism of Graphene with Vacancy Clusters
Graphene, a plane object composed of carbon atoms, is a perspective material for nanoelectronics and spintronics because of its unique electron and magnetic properties. It was found that graphene reveals spin polarization effect, i.e. its magnetic features increase when crystal defects (vacancies and clusters of vacancies) are introduced. Systematic analysis is performed by ab initio simulation with the use of VASP program complex in order to state spin polarization dependence of graphene on the number vacancies in a cluster and on a cluster configuration.
Graphene
Vacancy Clusters
Magnetism
https://mpm.spbstu.ru/article/2010.12.4/
MPM_9_1_P04.pdf
RAR
RUS
35-41
Tamuliene
Institute of Theoretical Physics and Astronomy of Vilnius University
Vilnius, Lithuania
Vaišnoras
Vilnius Pedagogical University
Vilnius, Lithuania
Badenes
The Institute of Photonic Sciences
Castelldefels, Spain
Balevičius
Vilnius University
Vilnius, Lithuania
Point of View on Magnetic Properties of Con (n=6,8,10,12) Based on Quantum Chemistry Investigations
In this paper we present quantum chemical investigations on magnetic properties of several Co nanoparticles. Results of magnetizability, g-tenzor, and the nature of bond and charge distribution in the particles are also presented. The results obtained allow us to propose reasons due to which magnetic properties of small particles are different and speculate what affected them
Quantum Chemistry
Magnetic Properties
Co nanoparticles
https://mpm.spbstu.ru/article/2010.12.5/
MPM_9_1_P05.pdf
RAR
RUS
42-52
Juršėnas
Vilnius University
Vilnius, Lithuania
Merkelis
Vilnius University
Vilnius, Lithuania
Application of Symbolic Programming for Atomic Many-Body Theory
In the present paper a symbolic programming method for generation of the expansion–terms expressions of atomic stationary perturbation theory is presented by using Mathematica system. For this purpose the package named as NCoperators was developed. Producing the PT terms, this package accommodates the features of the RayleighSchrödinger perturbation theory, the second quantization method and angular momentum theory. The package is built in such a way that it could be applicable in various areas of theoretical atomic spectroscopy. Many functions of the NCoperators can be easily adapted for users to their own demand by transforming the functions developed easily. The package gives the possibility of generating formulas in a traditional output form. For some quantities the expressions obtained in Mathematica can be converted into C code. Although the NCoperators package was developed for Unix OS, it can be easily adopted for other OS if some of the parameters to be changed.
Symbolic programming method
Mathematica system
Atomic Many-Body Theory
https://mpm.spbstu.ru/article/2010.12.6/
MPM_9_1_P06.pdf
RAR
RUS
53-67
Breczko
University of Bialystok
Bialystok, Poland
V.V. Barkaline
Belarussian National Technical University,
Minsk, Belarus
Grechishkin
Tver State University
Tver, Russia
Nelayev
Belarusian State University of Informatics and Radioelectronics
Minsk, Belarus
Magnetic Properties of Ni2MnGa Alloy
The paper presents results of the computer simulations and experimental investigation of physical properties of Ni-Mn-Ga alloy. The study was performed using atomic force microscope. The chemical composition of researched specimens causes generation of martensite and austenite phases. Computer simulations are devoted to austenite phase.
Ni2MnGa
Alloys
Magnetic Properties
https://mpm.spbstu.ru/article/2010.12.7/
MPM_9_1_P07.pdf
RAR
RUS
68-74
Bogdanovich
Vilnius University
Vilnius, Lithuania
Štikonas
Vilnius University
Vilnius, Lithuania
Rancova
Vilnius University
Vilnius, Lithuania
Comparison of Partial Diagonalization of Matrices with Standard Program Complexes
Effectiveness of the method of partial diagonalization of matrices created in Department of Theory of Atom at Institute of Theoretical Physics and Astronomy is compared with efficiency of application of corresponding programs from LAPACK and PRIMME libraries.
Partial Diagonalization of Matrices
Standard Program Complexes
LAPACK
PRIMME
https://mpm.spbstu.ru/article/2010.12.8/
MPM_9_1_P08.pdf
RAR
RUS
75-83
Kus
University of Warmia and Mazury in Olsztyn
Olsztyn, Poland
Breczko
University of Bialystok
Bialystok, Poland
DSC-Investigations of the Effect of Annealing Temperature on the Phase Transformation Behaviour in Ni-Ti Shape Memory Alloy
The variations in thermal transformation properties due to annealing within the temperature range from 400°C to 600°C were studied for the near equiatomic Ni-Ti shape memory alloy by the Differential Scanning Calorimetry (DSC) measurements. There was a critical temperature (about 600ºC), where the specimens demonstrated remarkably different transformation courses. There were also noticeable changes in transformation temperatures and heats depending on the annealing temperature. It is thought that the alterations of the microstructure in the Ni-Ti alloy during annealing are responsible for such behavior.
Ni-Ti
Shape Memory Alloy
Phase Transformation
Annealing
DSC
https://mpm.spbstu.ru/article/2010.12.9/
MPM_9_1_P09.pdf