X-ray Rietveld structure refinement of Sb3O6.5

Anchoring Sb6O13 Nanocrystals on Graphene Sheets for Enhanced Lithium Storage

“…33-0111), which suggested the Sb 6 O 13 was successfully synthesized via solvothermal method using Sb 2 O 3 and GO as raw materials. The crystal structure of Sb 6 O 13 is shown in Figure b as a defective pyrochlore-tye structure with structural formula of Sb 3+ Sb 5+ 2 O 6 O′ 0.5 , which contains the rigid (Sb 5+ O 3 ) framework and the (Sb 3+ 2 O′) framework . It is interesting that the diffraction peak at 2θ = 10° for GO (Figure S1a, black curve) disappeared and a wide diffraction peak at 2θ = 22° for rGO (Figure S1a, blue curve) appeared in the as-obtained Sb 6 O 13 /rGO sample, confirming that the GO was reduced into rGO during the preparation process of the Sb 6 O 13 /rGO sample.…”

A comprehensive examination of the local- and long-range structure of Sb6O13 pyrochlore oxide

“…After revealing its pyrochlore nature with a prompt peak indexing over a laboratory XRD pattern, displayed in Fig. 1a, a more exhaustive structural analysis was carried out in the Fd3m (# 227) space group, origin choice # 2, as previously reported for this material 22 , by means of extensive combined Rietveld refinement from SXRD and NPD diffraction data. Patterns obtained with both techniques established sharp diffraction peaks, characteristic of a cubic pyrochlore with Fig.…”

“…Indeed, in Sb 6 O 13 , the distribution of Sb 3+ ions at 96g instead of 16c Wyckoff positions is presumably due to the lone electron pair and its stereochemical effect, that would displace, by repulsion forces, the Sb′ atom about 0.353(9) Å from the (0,0,0) position to an adjacent 96g (x,x,z) site, with six-times greater multiplicity. The constrained SOF's values, chosen from previous reports 22 , were selected to get a coherent and electrically neutral formula, and they stand in reasonable agreement with those obtained from XANES, see more details below. Furthermore, we confirm that any attempt to add H + atoms systematically failed, proving the absence of water in the material, which is consistent with the results reported from pioneering analyses performed by Stewart et al 21 .…”

On the accurate bond-valence parameters for the Sb3+/O2−ion pair

“…The results presented here were obtained in the summer of 2009, when the above article of Mills et al (2009) had not yet been published. Being involved in the systematic investigations of the ternary systems Hg(Pb,Zn)-Sb-O (Sidey et al, 2008(Sidey et al, , 2010, and being interested in the development of reliable schemes for determining the high-quality BV parameters, the author of the present work decided to derive, as accurately as possible, the BV parameters for the Sb 3+ /O 2À ion pair from the precisely determined crystal structures. The main reason for this work was the fact that the r 0 and b parameters obtained for the Sb 3+ /O 2À ion pair from the corresponding Brown-Wu parameters r 0 and n (Brown & Wu, 1976;Sidey, 2009a) were based on the outdated structural information available in the mid 1970s.…”