Unveiling the electronic structures and optical properties of alkaline-earth oxides–modified silicate glasses

The electronic structure, interatomic bonding, and optical properties of mixed alkaline-earth metal oxides MO (M = Mg, Ca) on amorphous silica glasses were calculated by combined ab initio molecular dynamics and the orthogonalized linear combination of atomic orbitals approaches. With the addition of alkaline-earth metal oxides, the original structural network model is destroyed, nonbridging oxygen is generated, and the covalent bonding is reduced, which reduces the total bond order density for silicate glass. The complex dielectric function plot shows that there are three distinct peaks in the imaginary part of the original silica glasses, and the last two peaks level off with the modification of alkaline earth oxides.