The Y-Ag-Ga system

The isothermal section at 670 K of the Y-Ag-Ga system in the region of 0-33 at.% Y has been constructed using X-ray diffraction data. The existence of earlier known ternary gallides has been confirmed. Their homogeneity regions, atomic coordinates and distribution of atoms in the structures have been determined: Y3Ag2.55Ga8.45 (La3Al11-type structure, a = 0.4310(1) nm, b = 1.2865(3) nm, c = 0.9552(3) nm, RF = 0.043), YAg0.22Ga1.78 (CaIn2-type structure, a = 0.44565(1) nm, c = 0.72032(2) nm, RI = 0.081), YAg0.74Ga1.26 (KHg2-type structure, a = 0.45302(2) nm, b = 0.70805(3) nm, c = 0.78056(3) nm, RI = 0.059). The crystal structure of the new ternary compound YAg1.1Ga1.9 (β-YbAgGa2-type structure, Pnma, a = 0.69654(3) nm, b = 0.43391(2) nm, c = 1.02126(5) nm, RI = 0.087) has been studied for the first time.