Structure and properties of Cs containing borosilicate glasses studied by molecular dynamics simulations

摘要

Borosilicate glass is a very suitable matrix for immobilisation of nuclear waste. The major fission product in this waste is Cs-137 In the paper molecular dynamics simulations were used to study the influence of the gradual substitution of Na+ by Cs+. The caesium influence on the glass network Si and Al environment was relatively small. The biggest changes were observed in the case of B first neighbourhood. The boron coordination number and B-O bond length were linearly decreasing. In the studied glasses both sodium and caesium were mainly charge compensators of [AlO4] and [BO4] tetrahedra. The glass modifier structure was investigated using Voronoi analysis. There was observed aggregation and clustering of modifiers which was amplified by caesium substitution. (C) 2014 Elsevier B.V. All rights reserved.