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Two new Rb-Ga arsenates: RbGa(HAsO₄)₂ and RbGa₂As(HAsO₄)₆.

ABSTRACT: The crystal structures of hydro-thermally synthesized (T = 493?K, 7-9?d) rubidium gallium bis-[hydrogenarsenate(V)], RbGa(HAsO₄)₂, and rubidium digallium arsenic(V) hexa-[hydrogenarsenate(V)], RbGa₂As(HAsO₄)₆, were solved by single-crystal X-ray diffraction. Both compounds have tetra-hedral-octa-hedral framework topologies. The M⁺ cations are located in channels of the respective framework. RbGa(HAsO₄)₂ crystallizes in the RbFe(HPO₄)₂ structure type (Rc), while RbGa₂As(HAsO₄)₆ adopts the structure type of RbAl₂As(HAsO₄)₆ (Rc), which represents a modification of the RbFe(HPO₄)₂ structure type. In this modification, one third of the M³⁺O₆ octa-hedra are replaced by AsO₆ octa-hedra, and two thirds of the voids in the structure, which are usually filled by M⁺ cations, remain empty to achieve charge balance.

SUBMITTER: Schwendtner K

PROVIDER: S-EPMC6127722 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Two new Rb-Ga arsenates: RbGa(HAsO4)2 and RbGa2As(HAsO4)6.

Schwendtner Karolina K Kolitsch Uwe U

Acta crystallographica. Section E, Crystallographic communications 20180814 Pt 9

The crystal structures of hydro-thermally synthesized (T = 493 K, 7-9 d) rubidium gallium bis-[hydrogenarsenate(V)], RbGa(HAsO4)2, and rubidium digallium arsenic(V) hexa-[hydrogenarsenate(V)], RbGa2As(HAsO4)6, were solved by single-crystal X-ray diffraction. Both compounds have tetra-hedral-octa-hedral framework topologies. The M+ cations are located in channels of the respective framework. RbGa(HAsO4)<sub ...[more]

PMID: 30225109

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