论文标题
Lennard-Jones粒子在两个维度
Phase behaviour of Lennard-Jones particles in two dimensions
论文作者
论文摘要
仍对原型二维Lennard-Jones系统的相图进行了争议。特别是，文献中存在有争议的结果，这是涉及象牙阶段和熔化场景的存在。在这里，我们通过大规模数值模拟研究了2D LJ颗粒的相行为。我们证明，在高温下，当潜在的吸引力起着较小的作用时，熔化是通过连续的固体过渡发生的，然后是一阶己酸化合物跃迁。随着温度的降低，发生近晶相的密度范围会收缩，因此在低温熔融时通过一阶液体固定过渡发生。六角相消失的温度远高于液态气体临界温度。拓扑缺陷密度的演变证实了这种情况。
The phase diagram of the prototypical two-dimensional Lennard-Jones system, while extensively investigated, is still debated. In particular, there are controversial results in the literature as concern the existence of the hexatic phase and the melting scenario. Here, we study the phase behaviour of 2D LJ particles via large-scale numerical simulations. We demonstrate that at high temperature, when the attraction in the potential plays a minor role, melting occurs via a continuous solid-hexatic transition followed by a first-order hexatic-fluid transition. As the temperature decreases, the density range where the hexatic phase occurs shrinks so that at low-temperature melting occurs via a first-order liquid-solid transition. The temperature where the hexatic phase disappears is well above the liquid-gas critical temperature. The evolution of the density of topological defects confirms this scenario.
