The 79th JSAP Autumn Meeting, 2018

Presentation information

Symposium (Oral)

Symposium » The forefront of silica glass

[20p-432-1~8] The forefront of silica glass

Thu. Sep 20, 2018 2:00 PM - 6:00 PM 432 (432)

Koichi Kajihara(Tokyo Metropolitan Univ.), Akira Saitoh(Ehime Univ.)

3:45 PM - 4:15 PM

[20p-432-4] Slow dynamics of glass-forming liquids: A comprehensive analysis from silica to metallic glasses using molecular dynamics simulations

Kang Kim1 (1.Osaka Univ.)

Keywords:glass transition, supercooled liquids, molecular dynamics simulations

We perform molecular dynamics simulations for a silica glass former model proposed over a wide range of densities. The density variation can be mapped onto the change of the potential depth between Si and O interactions of this model. By reducing the potential depth (or increasing the density), the anisotropic tetrahedral network structure transforms into the isotropic structure with the purely repulsive soft-sphere potential. Correspondingly, the temperature dependence of the relaxation time exhibits the crossover from Arrhenius to super-Arrhenius behavior. Being able to control the fragility over a wide range by tuning the potential of a single model system helps us to bridge the gap between the network and isotropic glass formers and to obtain the insight into the underlying mechanism of the fragility.