Insight into the structure of vanadium containing glasses: A molecular dynamics study

Journal of Non-Crystalline Solids (Impact Factor: 1.77). 07/2011; DOI: 10.1016/j.jnoncrysol.2011.02.002


In this manuscript, classical molecular dynamics simulations (MD) have been applied to study the short and medium range order of very complex vanadium containing glasses with the aim of improving the first microscopic picture of such materials. A rigid ionic force-field has been extended to include the V(5+)-O, V(4+)-O and Cu(2+)-O interatomic pair parameters and tested to reproduce structural properties of known crystal phases with quite good accuracy. Then the structure of Na(2)O-SiO(2), CaO-MgO-Al(2)O(3)-SiO(2) and Na(2)O-P(2)O(5) glass compositions in which vanadium is present in the range 1-72 wt.% (0.3-60 mol.%) have been fully described in terms of vanadium local structure and Qn distributions. A fairly good agreement was found with experimental data further validating our computational models and providing a computational approach that could be used and extend to investigate in detail the structural information (V-V distances, V-O-V linkages and BO/NBO) directly correlated to macroscopic properties of application interest.

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    • "Z i , Z j are the partial charges of atoms i and j, D ij , a ij and R 0 are the Morse potential parameters. The original Pedone FF did not include the V\O parameters, which were later developed by Ori et al. [27] using a well-validated method based on the fitting of the parameters on crystalline structures [29]. All the parameters and the partial charge of the ions are summarised in Table 2. "
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