Jung Gerhard, Franosch Thomas
Institut für Theoretische Physik, Universität Innsbruck, 6020 Innsbruck, Austria.
Laboratoire Charles Coulomb (L2C), Université de Montpellier, CNRS, 34095 Montpellier, France.
Phys Rev E. 2022 Jul;106(1-1):014614. doi: 10.1103/PhysRevE.106.014614.
We simulate a hard-sphere liquid in confined geometry where the separation of the two parallel, hard walls is smaller than two particle diameters. By systematically reducing the wall separation we analyze the behavior of structural and thermodynamic properties, such as inhomogeneous density profiles, structure factors, and compressibilities when approaching the two-dimensional limit. In agreement with asymptotic predictions, we find for quasi-two-dimensional fluids that the density profile becomes parabolic and the structure factor converges toward its two-dimensional counterpart. To extract the compressibility in polydisperse samples a perturbative expression is used which qualitatively influences the observed nonmonotonic dependence of the compressibility with wall separation. We also present theoretical calculations based on fundamental-measure theory and integral-equation theory, which are in very good agreement with the simulation results.
我们在受限几何结构中模拟了一种硬球液体，其中两个平行硬壁之间的间距小于两个粒子直径。通过系统地减小壁间距，我们分析了结构和热力学性质的行为，例如接近二维极限时的非均匀密度分布、结构因子和压缩性。与渐近预测一致，我们发现对于准二维流体，密度分布变为抛物线形，结构因子收敛于其二维对应物。为了提取多分散样品中的压缩性，使用了一个微扰表达式，它定性地影响了观察到的压缩性随壁间距的非单调依赖性。我们还给出了基于基本度量理论和积分方程理论的理论计算结果，它们与模拟结果非常吻合。
