tailieunhanh - Pressure dependent structural heterogeneity in calcium silicate glass

This work presents a molecular dynamics simulation (MDS) of CaSiO3 glass using Born–Mayer–Huggins potentials. The structural organization and structural phase transition under compression as well as network structure of CaSiO3 are clarified through analysis and visualization of molecular dynamics simulation data. | JOURNAL OF SCIENCE OF HNUE DOI Mathematical and Physical Sci. 2016 Vol. 61 No. 7 pp. 165-175 This paper is available online at http PRESSURE-DEPENDENT STRUCTURAL HETEROGENEITY IN CALCIUM SILICATE GLASS Mai Thi Lan1 Nguyen Thi Thanh Ha1 Tran Thuy Duong1 Nguyen Thi Thao2 and Nguyen Van Hong1 1 School of Engineering Physics Hanoi University of Science and Technology 2 Hanoi University of Education Abstract. This work presents a molecular dynamics simulation MDS of CaSiO3 glass using Born Mayer Huggins potentials. The structural organization and structural phase transition under compression as well as network structure of CaSiO3 are clarified through analysis and visualization of molecular dynamics simulation data. The short-range order structure intermediate-range order structure are investigated in detail through analysis the pair of radial distribution function the coordination number distribution in TOn polyedra and OTm linkages n 4 11 m 2 5 T Si Ca . Topology structure of TOn and OTm is also clarified by investigating bond angle and bond length distribution in TOn polyhedra and OTm linkages. Keywords Structure phase transition polymerization molecular dynamics simulation CaSiO3 . 1. Introduction Calcium silicate CaSiO3 is one of the members of Pyroxene which is the main component of Basalt. The CaSiO3 is one of main components of the Earth s lower mantle. It is the important component in the glass and ceramic materials 1-4 . Knowledge of structure of CaSiO3 system in both glass and liquid states under high pressure is necessary for understanding about volcanic activity the physicochemical and thermal change of the Earth as well as controlling and completing the process of new material fabrication technology. CaSiO3 system has widely been studied for a long time by both theoretical and experimental methods 1 5-9 . However experiment is usually difficult to do at high temperature and pressure due to the high melting .