Crystal structure of K0.75[FeII3.75FeIII1.25(HPO3)6]·0.5H2O, an open-framework iron phosphite with mixed-valent FeII/FeIII ions

Acta Crystallographica Section E: Crystallographic Communications

Legarra, E.¹  Aguayo, A.T.²  Larrea, E.S.³  Arriortua, M.I.³  Mesa, J.L.⁴ 

[1] Basque Center for Materials, Applications & Nanostructures (BCMaterials), Parque Tecnológico de Zamudio, Camino de Ibaizabal, Edificio 500-1°, 48160 Derio, Spain;Dpto. Ingeniería Química, Universidad del País Vasco, UPV/EHU, Sarrina s/n, 48940 Leioa, Spain;Dpto. Mineralogía y Petrología, Universidad del País Vasco, UPV/EHU, Sarrina s/n, 48940 Leioa, Spain;Dpto. Química Inorgánica, Universidad del País Vasco, UPV/EHU, Sarrina s/n, 48940 Leioa, Spain

关键词: CRYSTAL STRUCTURE;    OPEN-FRAMEWORK STRUCTURE;    HYDROTHERMAL SYNTHESIS;    MIXED-VALENT FEII/FEIII COMPOUND;    ISOTYPISM;   

DOI  :  10.1107/S2056989015024007

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

Single crystals of the title compound, potassium hexa­phosphito­penta­ferrate(II,III) hemihydrate, K0.75[FeII3.75FeIII1.25(HPO3)6]·0.5H2O, were grown under mild hydro­thermal conditions. The crystal structure is isotypic with Li1.43[FeII4.43FeIII0.57(HPO3)6]·1.5H2O and (NH4)2[FeII5(HPO3)6] and exhibits a [FeII3.75FeIII1.25(HPO3)6]0.75− open framework with disordered K+ (occupancy 3/4) as counter-cations. The anionic framework is based on (001) sheets of two [FeO6] octa­hedra (one with point group symmetry 3.. and one with point group symmetry .2.) linked along [001] through [HPO3]2− oxoanions. Each sheet is constructed from 12-membered rings of edge-sharing [FeO6] octa­hedra, giving rise to channels with a radius of ca 3.1 Å where the K+ cations and likewise disordered water mol­ecules (occupancy 1/4) are located. O⋯O contacts between the water mol­ecule and framework O atoms of 2.864 (5) Å indicate hydrogen-bonding inter­actions of medium strength. The infrared spectrum of the compound shows vibrational bands typical for phosphite and water groups. The Mössbauer spectrum is in accordance with the presence of FeII and FeIII ions.

【 授权许可】

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