EVIDENCE FOR ALGEBRAIC ORIENTATIONAL ORDER IN A 2-DIMENSIONAL HARD-CORE NEMATIC
EVIDENCE FOR ALGEBRAIC ORIENTATIONAL ORDER IN A 2-DIMENSIONAL HARD-CORE NEMATIC
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DOI：
10.1103/physreva.31.1776
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发表时间：
1985-01-01
影响因子：
2.9
通讯作者：
EPPENGA, R
中科院分区：
文献类型：
--
作者：
FRENKEL, D;EPPENGA, R
本文对N个长度为L（N ≤ 3200）的无限细硬棒组成的二维流体进行了Monte Carlo模拟。该体系在低密度下具有各向同性相，在高密度下具有"β"相。虽然真正的长程取向顺序不排除先验，模拟表明，双相具有代数顺序。我们没有发现一阶各向同性的过渡的证据，相反，所有可用的证据指向发生的向错解约束的过渡的Kosterlitz无齿型。热容量CP峰值密度低于约20%的估计向错-非约束的转变点。我们讨论了早期的模拟2D向列相在目前的结果。我们计算了硬针流体的维里系数直到B 5，发现B 4很小，而B 5为负值。
We present Monte Carlo simulations on a two-dimensional (2D) fluid of N infinitely thin hard rods of length L (N≤ 3200). This system has an isotropic phase at low densities and a ‘‘nematic’’phase at high densities. Although true long-range orientational order is not excluded a priori, the simulations indicate that the nematic phase has algebraic order. We find no evidence for a first-order isotropic-nematic transition; rather, all the available evidence points towards the occurrence of a disclination-unbinding transition of the Kosterlitz-Thouless type. The heat capacity C P peaks at a density some 20% below the estimated disclination-unbinding transition point. We discuss earlier simulations on 2D nematics in the light of the current results. We have computed the virial coefficients of the hard-needle fluid up to B 5 and find that B 4 is very small, while B 5 is negative.