High-energy X-ray diffraction and reverse Monte Carlo simulation of xBi_O3-(100-X)TeO₂ glass and anti-glass phases

The structure of glass and anti-glass samples from the system: xBi_O3-(100-X)TeO₂ (x = 3,5,7 and 20-mol %) were studied using X-ray diffraction experiments at High Energy Materials Science Beamline of the PETRA synchrotron. The diffraction data was analysed by Reverse Monte Carlo (RMC) simulations and short range structural properties such as the near-neighbour distances the Te-O co-ordination (NT_e-o), distribution of bond lengths and bond angles in glass, and anti-glass phases of the Bi₂O₁-TeO₂ system were determined. The structural refinement confirms the presence of BiO₅, TeO₃ and TeO₄ units in Bi₂Te₄O₁₁ with the average NT_e-O and NB_io values of 3.31 and 4.22, respectively. The bond lengths of Te-O_bridging and Te-O_non-bridging were calculated to be 1.94 Å and 2.03 Å, respectively