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Safflorite, (Co,Ni,Fe)As(2), isomorphous with marcasite.

ABSTRACT: Safflorite, a naturally occurring cobalt-nickel-iron diarsenide (Co,Ni,Fe)As(2), possesses the marcasite-type structure, with cations (M = Co + Ni + Fe) at site symmetry 2/m and As anions at m. The MAs(6) octa-hedra share two edges, forming chains parallel to c. The chemical formula for safflorite should be expressed as (Co,Ni,Fe)As(2), rather than the end-member format CoAs(2), as its structure stabilization requires the simultaneous inter-action of the electronic states of Co, Ni, and Fe with As(2) (2-) dianions.

SUBMITTER: Yang H

PROVIDER: S-EPMC2960506 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Safflorite, (Co,Ni,Fe)As(2), isomorphous with marcasite.

Yang Hexiong H Downs Robert T RT Eichler Carla C

Acta crystallographica. Section E, Structure reports online 20080823 Pt 9

Safflorite, a naturally occurring cobalt-nickel-iron diarsenide (Co,Ni,Fe)As(2), possesses the marcasite-type structure, with cations (M = Co + Ni + Fe) at site symmetry 2/m and As anions at m. The MAs(6) octa-hedra share two edges, forming chains parallel to c. The chemical formula for safflorite should be expressed as (Co,Ni,Fe)As(2), rather than the end-member format CoAs(2), as its structure stabilization requires the simultaneous inter-action of the electronic states of Co, Ni, and Fe with ...[more]

PMID: 21201568

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