Wyniki wyszukiwania - BazTech

Ograniczanie wyników

1 International Journal of Applied Mechanics and Engineering

1 2002

Znaleziono wyników: 1

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Computation of transport and equilibrium properties of molecular systems with quantum mechanical calculation of interaction potentials

Arefiev K. M., Shevkunov S. V.

International Journal of Applied Mechanics and Engineering

2002

Vol. 7, no 4

1095-1123

The computation of transport coefficients in gases on the basis of molecular theory requires the determination of interaction potentials. As a rule, the dependencies of interaction energy on the distances between the molecules extracted from experimental data on different measurable characteristics are used. At the same time, direct calculation of interaction potentials on the basis of approximate solution of Schroedinger equation is possible for a number of relatively simple in their electron structure, but important for applications systems. Mixtures of the vapors of the atoms of metals with noble gases represent a typical example of such systems. In this paper, a comparison between experimental and calculated diffusion coefficients of the vapors of metals in the first and the second groups of Periodic Table dissolved in noble gases is presented. A sufficient for practical needs convergence of numerical results is demonstrated. The interaction potentials obtained can be used in the calculations of other transport coefficients, such as viscosity and thermal conductivity, in the mixtures of the vapors of metals with gases. Along with the traditional approach based on Schroedinger formalism, modern alternative methods of quantum mechanics and quantum statistics are presented. One example is the Path Integral Monte Carlo method based on Feynman representation of quantum mechanics. This formalism makes it possible to solve quantum statistical problems for thermally excited electron states and in this way to simulate numerically equilibrium properties of dense non-ideal plasma. Exchange and all correlation effects can be described in this formalism in an explicit way. Another modern approach aimed at stochastic simulations of electron quantum states is the so-called Diffusion Method, representing a solution of Schroedinger equation in imaginary time. Applications of stochastic methods in the problems of thermodynamics and plasma physics are presented. The perspectives and possible directions of development of new methods in the statistical description of condensed matter is briefly discussed.