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Updated: Sep 9, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Crystal structure of the 'missing' inter-metallic compound BaCu5
Kiran Avinash1, Justin Andrews1
1Department of Chemistry, Purdue University, 560 Oval Dr., West Lafayette, IN 47907-2084, USA.
Abstract:
The copper-rich inter-metallic compounds CaCu5 and SrCu5 are isostructural but the isomorphous compound BaCu5 (barium penta-copper) has not been reported. The absence of any compound with the composition of BaCu5 in the Ba-Cu phase diagram has previously been attributed to much larger radius of Ba. The structure of BaCu5, which crystallizes in an ortho-rhom-bic cell (space group Pnma) with the rare SrZn5 structure type is now reported The structure is characterized by a zigzag arrangement of infinite Ba chains ensconced in a Cu matrix. The Ba atom and three Cu atoms lie on special positions with m site symmetry and one Cu atom lies on a general crystallographic position.
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