TY - JOUR

T1 - Thermodynamics and phase transitions of electrolytes on lattices with different discretization parameters

AU - Artyomov, Maxim N.

AU - Kolomeisky, Anatoly B.

N1 - Funding Information:
The authors would like to acknowledge the support from the Welch Foundation (grant C-1559), the Alfred P. Sloan foundation (grant BR-4418) and the US National Science Foundation (grant CHE-0237105). The authors are also grateful to M.E. Fisher for valuable discussions, critical comments and encouragements.

PY - 2005/11/1

Y1 - 2005/11/1

N2 - Lattice models are crucial for studying thermodynamic properties in many physical, biological and chemical systems. We investigate the lattice restricted primitive model (LRPM) of electrolytes with different discretization parameters in order to understand thermodynamics and the nature of phase transitions in systems with charged particles. A discretization parameter is defined as a number of lattice sites that can be occupied by each particle, and it allows one to study the transition from the discrete picture to the continuum-space description. Explicit analytic and numerical calculations are performed using the lattice Debye-Hückel approach, which takes into account the formation of dipoles, the dipole-ion interactions and correct lattice Coulomb potentials. The gas-liquid phase separation is found at low densities of charged particles for different types of lattices. The increase in the discretization parameter lowers the critical temperature and the critical density, in agreement with Monte Carlo computer simulation results. In the limit of infinitely large discretization our results approach the predictions from the continuum model of electrolytes. However, for the very fine discretization, where each particle can only occupy one lattice site, the gas-liquid phase transitions are suppressed by order-disorder phase transformations.

AB - Lattice models are crucial for studying thermodynamic properties in many physical, biological and chemical systems. We investigate the lattice restricted primitive model (LRPM) of electrolytes with different discretization parameters in order to understand thermodynamics and the nature of phase transitions in systems with charged particles. A discretization parameter is defined as a number of lattice sites that can be occupied by each particle, and it allows one to study the transition from the discrete picture to the continuum-space description. Explicit analytic and numerical calculations are performed using the lattice Debye-Hückel approach, which takes into account the formation of dipoles, the dipole-ion interactions and correct lattice Coulomb potentials. The gas-liquid phase separation is found at low densities of charged particles for different types of lattices. The increase in the discretization parameter lowers the critical temperature and the critical density, in agreement with Monte Carlo computer simulation results. In the limit of infinitely large discretization our results approach the predictions from the continuum model of electrolytes. However, for the very fine discretization, where each particle can only occupy one lattice site, the gas-liquid phase transitions are suppressed by order-disorder phase transformations.

UR - http://www.scopus.com/inward/record.url?scp=31744441249&partnerID=8YFLogxK

U2 - 10.1080/00268970500142683

DO - 10.1080/00268970500142683

M3 - Article

AN - SCOPUS:31744441249

VL - 103

SP - 2863

EP - 2872

JO - Molecular Physics

JF - Molecular Physics

SN - 0026-8976

IS - 21-23 SPEC. ISS.

ER -