Apolinario S W S, Aguiar J Albino, Peeters F M
Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE, Brazil.
Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Dec;90(6):063113. doi: 10.1103/PhysRevE.90.063113. Epub 2014 Dec 29.
Molecular-dynamic simulations were performed in order to investigate the melting processes of isotropically confined binary systems. We considered two species of particles, which differ by their amount of electric charge. A Lindemann type of criterion was used to determine the angular melting temperature. We demonstrate that the magic-to-normal cluster transition can evolve in two distinct ways, that is, through a structural phase transition of the first order or via a smooth transition where an increase of the shells' width leads to a continuous decreasing mechanical stability of the system. Moreover, for large systems, we demonstrate that the internal cluster exerts a minor effect on the mechanical stability of the external shell. Furthermore, we show that highly symmetric configurations, such as those found for multiple ring structures, have large mechanical stability, i.e., high angular melting temperature.
为了研究各向同性受限二元体系的熔化过程，进行了分子动力学模拟。我们考虑了两种粒子，它们的电荷量不同。使用林德曼类型的判据来确定角熔化温度。我们证明，魔法团簇到正常团簇的转变可以通过两种不同的方式演化，即通过一级结构相变或通过平滑转变，其中壳层宽度的增加导致系统机械稳定性的持续下降。此外，对于大型系统，我们证明内部团簇对外壳的机械稳定性影响较小。此外，我们表明，高度对称的构型，如多环结构中的构型，具有较大的机械稳定性，即较高的角熔化温度。
