Mesoporous materials from SiO₂ and NiTiO₃

Effect of Sodium Oxide Modifier on Structural and Elastic Properties of Silicate Glass

“…In the pure silica glass case, MD simulations have shown that the structure of SiO 2 glass is based on a three-dimensional continuous random network of SiO 4 tetrahedra . This structure of glassy state is similar to that of the crystal state reported by many authors. − When this material is modified by adding different amounts of sodium oxide, these glasses are usually presumed to be mainly made of a network of SiO 4 tetrahedra that is disrupted by modifying cations, as shown in Figure . At the time of glass making by quenching the material from its equilibrium state at high temperature, the sodium atoms break Si–O bonds to produce NBOs, leading to the formation of interface zones between tetrahedra and thus resulting in depolymerization of the SiO 2 network.…”