Scientific Reports · 2020 · 16 citations · 37 references
Natural SciencesChemistryMaterials ScienceInorganic ChemistryMaterials ChemistrySolid-state ChemistryCrystal ChemistryCrystal SymmetryCrystallographyNeutron DiffractionX-ray CrystallographyX-ray DiffractionAntimony ChemistryCrystal Structure DeterminationCrystallographic CharacterizationExtended X-ray Absorption Fine StructureRietveld AnalysisRietveld RefinementX-ray Absorption Near Edge StructureX-ray Absorption Spectroscopy
Abstract The crystal structure of the Sb 6 O 13 oxide, exhibiting a defect pyrochlore crystal structure with atomic vacancies, has been studied using a complete set of state-of-the-art techniques. The degree of antimony disproportionation in Sb 3+ and Sb 5+ valence states has been directly determined around 36% and 64%, respectively, using X-ray absorption near edge structure (XANES). These findings are in excellent agreement with our Rietveld analysis of synchrotron X-ray (SXRD) and neutron powder diffraction (NPD) results. Moreover, the highly distorted Sb 3+ coordination due to its lone electron pair has been critically revisited. The bonding distances and coordination of Sb 3+ and Sb 5+ species closely agree with an extensive dynamic and crystallographic determination using the Extended X-ray Absorption Fine Structure (EXAFS) technique. Most importantly, the specific local disorder of the two distinctive Sb ions has been crosschecked monitoring their unusual Debye–Waller factors.
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