Modeling oxide glasses with Born-Mayer-Huggins potentials: Effect of composition on structural changes

Using Born-Mayer-Huggins potentials, a molecular dynamics model of a series of 5-oxide (SiO2, B2O3, Na2O, Al2O3, and ZrO2) glasses of various compositions was developed. The evolution of the glass structure according to the composition provides an overview of the behavior of each species. Some experimental observations were correctly reproduced, e.g., the gradual incorporation of the boron in the silicate network, the attraction of sodium atoms by four-coordinate boron, and the shorter distances between network formers and non-bridging oxygen atoms. Moreover, direct visualization of the structures reveals boron-enriched segregation zones in a composition containing no aluminum, as well as smaller regions comprising only aluminum atoms.