Synchrotron X-ray and neutron scattering studies of in situ heated BaO·2SiO₂ glasses

Synchrotron X-ray scattering and neutron scattering experiments are used to study structural changes in BaO∙2SiO₂ glasses that were in situ isothermally heated at multiple temperatures. The temperatures selected cover the nucleation temperature range in this glass. No systematic trend in the scattering results was observed as a function of either temperature or isothermal time in the neutron scattering results. In the synchrotron X-ray scattering experiments, the peak heights of the structure factor increased with increasing annealing time, indicating structural ordering, but only at the lowest temperature. A technique that jointly combines reverse Monte Carlo and molecular dynamics simulations is used to reveal the source of the structural ordering with annealing.