Crystal structures of the ternary compounds Yb(Ga,Si)_2-x

Chem. Met. Alloys 10 (2017) 30-39

https://doi.org/10.30970/cma10.0358

Taras DELENKO, Marina BOYKO, Natalia MUTS, Yaroslav TOKAYCHUK, Roman GLADYSHEVSKII

The existence of two ternary compounds with AlB₂- and α-ThSi₂-type structures was confirmed in the system Yb–Ga–Si at 600 and 500°C and their crystal structures were refined by the Rietveld method for different compositions. In addition, a new ternary phase was found at 500°C: YbGa_0.60(7)Si_1.27(7) (structure type GdSi_1.4, Pearson symbol oI12, space group Imma, a = 4.0646(5), b = 4.0634(4), c = 14.0796(9) Å). The structure types AlB₂, α-ThSi₂, and GdSi_1.4 are members of the family of structures with trigonal-prismatic coordination of the smaller atoms. Substitution of Si atoms for Ga atoms in the ternary phases leads to increased dimensionality of the network formed by the p‑element atoms.

Networks formed by the p-element atoms in the structures of the ternary compounds in the system Yb–Ga–Si.

Keywords

Ytterbium / Gallium / Silicon / X-ray powder diffraction / Crystal structure