Crystal structure of GdNi₃Ga₉

Chem. Met. Alloys 12 (2019) 21-28

https://doi.org/10.30970/cma12.0390

Viktor TOPERTSER, Romana-Iryna MARTYNIAK, Nataliya MUTS, Yaroslav TOKAYCHUK, Roman GLADYSHEVSKII

The crystal structure of the GdNi₃Ga₉ compound was refined on X-ray powder diffraction data collected for a sample of composition Gd_7.7Ni_23.1Ga_69.2. The phase composition determined by X-ray diffraction was confirmed by energy-dispersive X-ray spectroscopy. The refinement of the crystal structure of GdNi₃Ga₉ was carried using the structure model defined on DyNi₃Al₉ (Pearson symbol hR99, space group R32, a = 0.72624(1), c = 2.74876(5) nm). The structure type DyNi₃Al₉ is intermediate between the R_0.67Ni₂Al₆ type in space group P‑6m2 (statistical arrangement of rare-earth atoms and Al atom triangles), and the fully ordered structure type ErNi₃Al₉ with the same supercell and space group R32.

Representation of the relationship between the Yb_0.67Ni₂Al₆, DyNi₃Al₉ and ErNi₃Al₉ structure types.

Keywords

X-ray powder diffraction / Energy-dispersive X-ray spectroscopy / Crystal structure / GdNi₃Ga₉