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Non-isovalent substitution in a Zintl phase with the TiNiSi type structure, CaMg(1-x)Ag(x)Ge [x = 0.13 (3)].

ABSTRACT: Single crystals of the title Ag-substituted calcium magnesium germanide, CaMg(1-x)Ag(x)Ge [x = 0.13 (3)] were obtained from the reaction of the corresponding elements at high temperature. The compound crystallizes with the TiNiSi structure type (Pearson code oP12) and represents an Ag-substituted derivative of the Zintl phase CaMgGe in which a small fraction of the divalent Mg atoms have been replaced by monovalent Ag atoms. All three atoms in the asymmetric unit (Ca, Mg/Ag, Ge) occupy special positions with the same site symmetry (.m.). Although the end member CaAgGe has been reported in an isomorphic superstructure of the same TiNiSi type, higher Ag content in solid solutions could not be achieved due to competitive formation of other, perhaps more stable, phases.

SUBMITTER: Banenzoue C

PROVIDER: S-EPMC2971942 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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Non-isovalent substitution in a Zintl phase with the TiNiSi type structure, CaMg(1-x)Ag(x)Ge [x = 0.13 (3)].

Banenzoué Charles C Ponou Siméon S Lambi John Ngolui JN

Acta crystallographica. Section E, Structure reports online 20091121 Pt 12

Single crystals of the title Ag-substituted calcium magnesium germanide, CaMg(1-x)Ag(x)Ge [x = 0.13 (3)] were obtained from the reaction of the corresponding elements at high temperature. The compound crystallizes with the TiNiSi structure type (Pearson code oP12) and represents an Ag-substituted derivative of the Zintl phase CaMgGe in which a small fraction of the divalent Mg atoms have been replaced by monovalent Ag atoms. All three atoms in the asymmetric unit (Ca, Mg/Ag, Ge) occupy special p ...[more]

PMID: 21578545

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