Martin Seth C, Hansen-Goos Hendrik, Laird Brian B
Department of Chemistry, University of Kansas, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States.
Institute for Theoretical Physics, University of Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany.
J Phys Chem B. 2020 Sep 10;124(36):7938-7947. doi: 10.1021/acs.jpcb.0c04124. Epub 2020 Jul 22.
In this work, we examine the surface thermodynamics of a hard-disk fluid at curved hard walls using Monte Carlo (MC) simulation and a generalized scaled particle theory (gSPT). The curved walls are modeled as hard disks of varying radii, . The surface free energy, γ, and excess surface volume, , for this system are calculated as functions of both the fluid packing fraction and the wall radius. The simulation results are used to test, for this system, the assumptions of morphometric thermodynamics (MT), which predicts that both γ and are linear functions of the surface curvature, 1/, for a two-dimensional system. In addition, we compare the simulation results to the gSPT developed in this work, as well as with virial expansions derived from the known virial coefficients of the binary hard-sphere fluid. At low to intermediate packing fractions, the non-MT terms (terms of higher order than 1/ in a expansion of γ and ) of γ are zero within the simulation error; however, at the highest densities, deviations from MT become significant, similar to what was seen in our earlier simulation work on the three-dimensional hard-sphere/hard-wall system. In addition, the new gSPT gives improved results for both γ and over standard scaled particle theory (SPT) but underestimates the deviations from MT at high density.
在这项工作中，我们使用蒙特卡罗（MC）模拟和广义标度粒子理论（gSPT）研究了弯曲硬壁处硬磁盘流体的表面热力学。弯曲壁被建模为具有不同半径的硬磁盘。该系统的表面自由能γ和过量表面体积被计算为流体填充率和壁半径的函数。模拟结果用于检验该系统的形态计量热力学（MT）假设，该假设预测对于二维系统，γ和均为表面曲率1/的线性函数。此外，我们将模拟结果与本工作中开发的gSPT以及从二元硬球流体的已知维里系数导出的维里展开式进行了比较。在低至中等填充率下，γ的非MT项（γ展开式中高于1/的高阶项）在模拟误差范围内为零；然而，在最高密度下，与MT的偏差变得显著，这与我们早期对三维硬球/硬壁系统的模拟工作中所见类似。此外，新的gSPT在γ和方面比标准标度粒子理论（SPT）给出了更好的结果，但在高密度下低估了与MT的偏差。
