Structural and dynamic properties of soda–lime–silica in the liquid phase

• Published in: The Journal of chemical physics 2020-12, Vol.153 (21), p.214505-214505
• Main Authors: Serva, Alessandra, Guerault, Allan, Ishii, Yoshiki, Gouillart, Emmanuelle, Burov, Ekaterina, Salanne, Mathieu
• Format: Article
• Language: English
• Subjects: Bonding strength; Calcium ions; Chemical Physics; Deformation effects; Diffusion rate; Lime; Liquid phases; Molecular dynamics; Physics; Properties (attributes); Silica glass; Silicon dioxide; Sodium
• ISSN: 0021-9606; 1089-7690
• DOI: 10.1063/5.0029702

Soda–lime–silica is a glassy system of strong industrial interest. In order to characterize its liquid state properties, we performed molecular dynamics simulations employing an aspherical ion model that includes atomic polarization and deformation effects. They allowed us to study the structure and diffusion properties of the system at temperatures ranging from 1400 K to 3000 K. We show that Na+ and Ca2+ ions adopt a different structural organization within the silica network, with Ca2+ ions having a greater affinity for non-bridging oxygens than Na+. We further link this structural behavior to their different diffusivities, suggesting that escaping from the first oxygen coordination shell is the limiting step for the diffusion. Na+ diffuses faster than Ca2+ because it is bonded to a smaller number of non-bridging oxygens. The formed ionic bonds are also less strong in the case of Na+.