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Ba₅(IO₆)₂: crystal structure evolution from room temperature to 80 K.

ABSTRACT: The crystal structure of Ba₅(IO₆)₂, penta-barium bis-(orthoperiodate), has been re-investigated at room temperature based on single-crystal X-ray diffraction data. In comparison with a previous crystal structure determination by the Rietveld method, an improved precision of the structural parameters was achieved. Additionally, low-temperature measurements allowed the crystal structure evolution to be studied down to 80 K. No evidence of structural transition was found even at the lowest temperature. Upon cooling, the lattice contraction is more pronounced along the b axis. This contraction is found to be inhomogeneous along different crystallographic axes. The inter-atomic distances between different Ba atoms reduce drastically with lowering temperature, resulting in a closer packing around the IO₆ octa-hedra, which remain largely unaffected.

SUBMITTER: Bi DW

PROVIDER: S-EPMC8183445 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Ba5(IO6)2: crystal structure evolution from room temperature to 80 K.

Bi David Wenhua DW Baral Priya Ranjan PR Magrez Arnaud A

Acta crystallographica. Section E, Crystallographic communications 20210514 Pt 6

The crystal structure of Ba5(IO6)2, penta-barium bis-(orthoperiodate), has been re-investigated at room temperature based on single-crystal X-ray diffraction data. In comparison with a previous crystal structure determination by the Rietveld method, an improved precision of the structural parameters was achieved. Additionally, low-temperature measurements allowed the crystal structure evolution to be studied down to 80 K. No evidence of structural transition was ...[more]

PMID: 34164142

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