Densified silica glass study by RMC simulation using X-ray and neutron diffraction data

X線と中性子回析データを用いた高密度シリカグラスのRMCシミュレーション

Yagafarov, O.; 小原 真司*; Temleitner, L.*; 稲村 泰弘  ; 片山 芳則

Yagafarov, O.; Kohara, Shinji*; Temleitner, L.*; Inamura, Yasuhiro; Katayama, Yoshinori

In the nearest future it will be possible to complement high pressure X-ray measurements at synchrotrons with neutron diffraction study at J-PARC. One possible way to analyze both experimental data in combination is to use the Reverse Monte Carlo (RMC) algorithm to derive structures of disordered materials. Here we analyze previously measured X-ray and neutron diffraction data on densified silica glass SiO. High pressure study of this archetypal glass is still challenging. One of the main issues is understanding of permanent densification mechanism under compression. In order to verify topological changes by analyzing structures directly, we used RMC simulation to build 3D structural models of normal (2.2g/cm) and densified (2.45g/cm and 2.63g/cm) glass. Derived RMC models (each made of 6000 atoms) accurately reproduces the experimental data and gives reasonable rings statistics and bond angle distributions.