Representatives of the structure type MgCu4Sn in the {Zr,Hf}CuAg systems

 

Chem. Met. Alloys 8 (2015) 129-134

 

Mariya STANITSKA, Svitlana PUKAS, Karin CENZUAL, Roman GLADYSHEVSKII

 

Two ternary intermetallides, ZrCu4Ag and HfCu4Ag, were synthesized by arc melting and annealed at 600C; 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 ZrCu4.05(2)Ag0.95(2)), and a = 6.9133(1) Å for HfCu4Ag. The refinement indicated significant off-stoichiometry for the latter, HfCu4.22(1)Ag0.78(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