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MIn(HAsO₄)₂ (M = K, Rb, Cs): three new hydrogen-arsenates adopting two different structure types.

ABSTRACT: Potassium indium bis-[hydrogen arsenate(V)], KIn(HAsO₄)₂, rubidium indium bis-[hydrogen arsenate(V)], RbIn(HAsO₄)₂, and caesium indium bis-[hydrogen arsenate(V)], CsIn(HAsO₄)₂, were grown under mild hydro-thermal conditions (T = 493?K, 7-8?d). KIn(HAsO₄)₂ adopts the KSc(HAsO₄)₂ structure type (space group C2/c), while RbIn(HAsO₄)₂ and CsIn(HAsO₄)₂ crystallize in the space group R-3c and are the first arsenate representatives of the RbFe(HPO₄)₂ structure type. All three compounds have tetra-hedral-octa-hedral framework topologies. The M⁺ cations, located in voids of the respective framework, are slightly disordered in RbIn(HAsO₄)₂. In KIn(HAsO₄)₂, there is a second K-atom position with a very low occupancy, which may suggest that the K atom can easily move in the channels extending along [101].

SUBMITTER: Schwendtner K

PROVIDER: S-EPMC5730323 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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MIn(HAsO4)2 (M = K, Rb, Cs): three new hydrogen-arsenates adopting two different structure types.

Schwendtner Karolina K Kolitsch Uwe U

Acta crystallographica. Section E, Crystallographic communications 20170929 Pt 10

Potassium indium bis-[hydrogen arsenate(V)], KIn(HAsO4)2, rubidium indium bis-[hydrogen arsenate(V)], RbIn(HAsO4)2, and caesium indium bis-[hydrogen arsenate(V)], CsIn(HAsO4)2, were grown under mild hydro-thermal conditions (T = 493 K, 7-8 d). KIn(HAsO4)2 adopts the KSc(HAsO4)2 structure type (space group C2/c), while RbIn(HAsO4)2 and CsIn(HAsO< ...[more]

PMID: 29250386

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