Open AccessApproximation of Cluster Integrals for Various Lattice-Gas Models
Author(s) -
S. Yu. Ushcats,
M. V. Ushcats,
V. M. Sysoev,
D.A. Gavryushenko
Publication year - 2018
Publication title -
ukrainian journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.213
H-Index - 17
eISSN - 2071-0194
pISSN - 2071-0186
DOI - 10.15407/ujpe63.12.1066
Subject(s) - lattice (music) , radius of convergence , virial theorem , virial coefficient , physics , power series , cluster expansion , statistical physics , cluster (spacecraft) , boiling point , mathematical analysis , mathematics , mathematical physics , quantum mechanics , thermodynamics , galaxy , acoustics , computer science , programming language
An approximation for cluster integrals of an arbitrary high order has been proposed for the well-known lattice-gas model with an arbitrary geometry and dimensions. The approximation is based on the recently obtained accurate relations for the convergence radius of the virial power series in the activity parameter for the pressure and density. As compared to the previous studies of the symmetric virial expansions for the gaseous and condensed states of a lattice gas, the proposed approximation substantially approaches the pressure values at the saturation and boiling points. For the Lee–Yang lattice-gas model, the approximation considerably improves the convergence to the known exact solution.