Glass formation and structure evolution in the rapidly solidified monatomic metallic liquid Pt under high pressure

Abstract

In this paper, we have studied the local atomic structure as well as the effect of pressure on the structure of Platinum monatomic metallic glass using molecular dynamics simulations combined with the embedded atom method (EAM). To achieve our study, we have used the pair distribution function (PDF), Voronoi tessellation analysis and the coordination number. The Voronoi analysis revealed that the fraction of icosahedral-like and mixed-like clusters increases with the decrease of temperature during the cooling process. The splitting shown in the second peak of the PDF is then characterized indicating that it is not only attributed to the formation of the full icosahedral cluster, but also to the formation of other Voronoi polyhedrons. Moreover, it is found that at a cooling rate of 1013 K/s, amorphous structures are obtained for pressure that is not higher than 30 GPa and crystalline phases are obtained at 40 GPa. Voronoi tessellation analysis demonstrated that the local structure of the amorphous platinum changes when increasing pressure.