New interaction potentials for alkaline earth silicate and borate glasses

New interaction potentials were developed for molecular dynamics simulations to study the role of Mg and Ca in modifying the structure and properties of alkaline earth silicates and borates. Competition between the depolymerization of the silica network and the formation of new bonds between oxygen atoms and modifiers leads to the enhancement of the elastic moduli with increasing modifier content in alkaline earth silicate glasses. Compared with calcium silicate, the higher elastic moduli of magnesium silicate result from a higher connectivity of the overall glass network due to the incorporation of fourfold coordinated magnesium and a more rigid connection between oxygen atoms and modifiers. In contrast to the silicates, the effect of modifier on the elastic moduli of alkaline earth borates is dominated by the formation of fourfold coordinated boron (N4). Calcium borate with higher N4 shows a more rigid network structure and higher elastic moduli.

Automated summary

New interaction potentials were developed for molecular dynamics simulations to investigate the influence of Mg and Ca on alkaline earth silicates and borates. The elastic moduli of alkaline earth silicate glasses increase with higher modifier content, with magnesium contributing to higher connectivity and more rigid connections compared to calcium. In alkaline earth borates, the presence of N4 leads to a more rigid network structure and higher elastic moduli, particularly in calcium borate.