Crystal growth, structure elucidation and CHARDI/BVS investigations of ß-KCoFe(PO4)2.
Acta Crystallogr E Crystallogr Commun
; 78(Pt 7): 746-749, 2022 Jul 01.
Article
em En
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| ID: mdl-35855369
ABSTRACT
Single crystals of ß-KCoFe(PO4)2, potassium cobalt(II) iron(III) bis-(ortho-phosphate), were grown from the melt under atmospheric conditions. This phosphate crystallizes isotypically with KZnFe(PO4)2 in space group C2/c, adopting a zeolite-ABW type of structure. The structure of the present phosphate is distinguished by an occupational disorder of the two transition-metal sites with ratios FeCo of 0.57250.4275 for the first and 0.42750.5725 for the second site. In the crystal structure, PO4 and (Co,Fe)O4 tetra-hedra are linked through vertices to form elliptical rings with the sequence DDDDUUUU of up (U) and down (D) pointing vertices. Each eight-membered ring is surrounded by four other rings of the same type, delimiting inter-stices with rectangular shape. This arrangement leads to the formation of [(Co/Fe)(PO4)]- ∞ sheets parallel to (001). Stacking of the sheets into a three-dimensional framework results in the formation of two types of channels. The first one is occupied by potassium cations, whereas the second one remains vacant. Calculations of bond-valence sums and charge distribution were used to confirm the structure model.
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01-internacional
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MEDLINE
Idioma:
En
Revista:
Acta Crystallogr E Crystallogr Commun
Ano de publicação:
2022
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Article