Representatives of the structure type MgCu₄Sn in the {Zr,Hf}–Cu–Ag systems

Chem. Met. Alloys 8 (2015) 129-134

https://doi.org/10.30970/cma8.0332

Mariya STANITS’KA, Svitlana PUKAS, Karin CENZUAL, Roman GLADYSHEVSKII

Two ternary intermetallides, ZrCu₄Ag and HfCu₄Ag, were synthesized by arc melting and annealed at 600°C; their crystal structures were studied by X-ray powder diffraction. The structures belong to the family of Friauf-Laves phases and are isotypic to MgCu₄Sn: Pearson symbol cF24, space group F-43m, a = 6.9597(1) Å for ZrCu₄Ag (refined composition ZrCu_4.05(2)Ag_0.95(2)), and a = 6.9133(1) Å for HfCu₄Ag. The refinement indicated significant off-stoichiometry for the latter, HfCu_4.22(1)Ag_0.78(1). No deviation from cubic symmetry was detected.

Unit cell content and coordination polyhedra for ZrCu₄Ag

Keywords

Zirconium / Hafnium / Copper / Silver / X-ray powder diffraction / Crystal structure / Friauf-Laves phase