STRUCTURAL CHANGES IN ALKALI DEPLETED ALKALI-SILICATE GLASS - MD STUDY

摘要

Alkali-silicate glass irradiated with electrons of the medium energy becomes to be fully depleted of alkali ions after some time. The chemical changes are expected to be accompanied with significant changes of glass structure. The changes in structure of 15K_2O·85SiO_2 glass were simulated by ab-initio MD. Experimental conditions were imitated by the following procedure. First, glass was prepared by the numerical cooling from the high-temperature melt. Second, alkali ions were removed. Third, silica structure was relaxed at temperatures 300 K and 1000 K. Structural changes are characterized in terms PP RDF's and coordination numbers. It was found peroxide bonds were created from the dangling bonds, coming from non-bridging oxygen.