Structural characterization of neodymium containing glasses by molecular dynamics simulation

Structural characterization of neodymium containing glasses was performed by using molecular dynamic simulations. Chemical and physical properties of glasses are strongly related to the local environment of the different ions constituting the three dimensional network. In rare earth containing glasses the modifications of the basic structural units and the physical properties of the host material strongly depend on the rare earth ion content. In this work molecular dynamic simulations (MD) have been used to characterize the structural modification induced by the Nd3+ addition into a silicate glasses. The increase of the NBO species in the glass structure has been observed as a results of the increasing Nd2O3 content. This results compare well with the experimental evidences that indicates the glass depolymerization promoted by the neodymium addition. The structural length scale associated with the rare earth clustering process, experimentally observed, have been also investigated. MD results reveals the presence of Nd-O-Nd linkages which indicate the possibility of the rare earth cations to clusterize in the glass network. The presence of Nd3+ rich regions promotes the concentration quenching phenomena that are associated to the drastic changes in the glass amplification efficiency experimentally observed for neodymium containing glasses.