Anomalous melting scenario of the two-dimensional core-softened system

• Published in: Physical review letters Vol. 112; no. 15; p. 157803
• Main Authors: Dudalov, D E, Fomin, Yu D, Tsiok, E N, Ryzhov, V N
• Format: Journal Article
• Language: English
• Published: United States 18-04-2014
• Subjects: Compressing; Computational fluid dynamics; Density; Hexatic phases; Melting; Phase diagrams; Three dimensional; Two dimensional
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.112.157803

We present a computer simulation study of the phase behavior of two-dimensional (2D) classical particles repelling each other through an isotropic core-softened potential. As in the analogous three-dimensional (3D) case, a reentrant-melting transition occurs upon compression for not too high pressures, along with a spectrum of waterlike anomalies in the fluid phase. However, in two dimensions in the low density part of the phase diagram melting is a continuous two-stage transition, with an intermediate hexatic phase. All available evidence supports the Kosterlitz-Thouless-Halperin-Nelson-Young scenario for this melting transition. On the other hand, at the high density part of the phase diagram one first-order transition takes place.