Network structure of molybdate glasses by neutron and X-ray diffraction and reverse Monte Carlo modelling

Rare-earth molybdate glasses have been prepared by rapid quench technique, the network structure was investigated by neutron and high-energy X-ray diffraction. For data evaluation the reverse Monte Carlo simulation technique was applied to obtain a possible 3-dimensional network configuration, which is consistent with the experimental data. From the modelling the partial atomic correlation functions g(ij)(r) and the coordination number distributions CNij have been revealed. Formation of MoO4 (55%) and MoO6 (25%) units was established for the binary 90MoO(3)-10Nd(2)O(3) glass. The B-O first neighbour distribution show a relatively broad first neighbour distance at 1.40 angstrom, the average coordination numbers show the presents of trigonal BO3 and tetrahedral BO4 groups. For 50MoO(3)-25Nd(2)O(3)-25B(2)O(3) sample mixed MoO4-BO4 and MoO4-BO3 linkages form pronounced intermediate-range order.