Thermodynamics of a two-dimensional Yukawa fluid

Abstract

Thermodynamic quantities of a two-dimensional Yukawa system, a model for various systems including single-layered dust particles observed in dusty plasmas, are obtained and expressed by simple interpolation formulas. In the domain of weak coupling, the analytical method based on the cluster expansion is applied and, in the domain of intermediate and strong coupling, numerical simulations are performed. Due to reduced dimensionality, the treatment based on the mean field fails at the short range and exact behavior of the binary correlation is to be taken into account even in the case of weak coupling.

Thermodynamics of Yukawa fluids near the one-component-plasma limit

“…4 of Ref. [6] (again, including the regime Γ < ∼ 1 shown in the inset of this figure). Thus, simple and accurate practical tool to estimate thermodynamic properties of 2D Yukawa fluids is now available.…”

“…The latter can be calculated using the analytical results available in the literature (see e.g. [6]). However, this contribution is vanishingly small at Γ ≫ 1 and can be omitted.…”

“…[6] do not cover the regime of very strongly coupled fluids, near the fluidsolid phase transition. We, therefore, performed additional simulations for 2D Yukawa fluids near freezing.…”

“…Now, by analogy with approach discussed in the previous section, we apply the observed soft-repulsion scaling of u th to evaluate the excess energy of weakly screened Yukawa systems in 2D geometry. The static component of the excess energy is associated with the triangular lattice sum (Madelung energy), which for the Yukawa interaction can be approximated by [6] u M ≃ −1.1061Γ 1 − 0.4555κ + 0.0999κ 2 − 0.0087κ 3 .…”

“…Thermodynamic properties have also received considerable attention. The accurate results from Monte Carlo (MC) and molecular dynamics (MD) numerical simulations for some thermodynamic functions (in particular, for internal energy and compressibility) have been tabulated for a wide (but discrete) range of state variables Γ and κ [1][2][3][4][5][6]. Recently, simple and accurate expressions to evaluate thermodynamic properties of three-dimensional (3D) Yukawa fluids [7] and solids [8] have been proposed, which are very convenient for practical applications.…”