Multi-component amorphous glasses: effect of glass compositions

Selection of suitable glass composition for vitrification of high level radioactive waste (HLWs) is one of the major challenges in nuclear waste reprocessing. Atomic and molecular level understanding can help in preliminary screening and thus reduce the dependency to some extent on tedious experimental procedures. In that context, extensive molecular dynamics (MD) have been carried out, which provides microscopic understanding of the glass structure and phenomena associated with the change in glass compositions. A detailed view of local structure and medium range connectivity has been explored. Results showed a good match of evaluated macroscopic glass parameters: density (ρ), glass transition temperature (T_g) and thermal expansion coefficient (TEC) with the experiments. The presented results might be of great scientific use for future glasses in various applications including nuclear waste immobilization. (author)