The ternary system SmGaSn: isothermal section of the phase diagram at 600C and crystal structures of the compounds

 

Chem. Met. Alloys 8 (2015) 112-122

 

Yaroslav TOKAYCHUK

 

The isothermal section at 600C of the phase diagram of the ternary system SmGaSn was constructed using X-ray powder diffraction data. Limited solid solutions based on the binary compounds SmSn3 (30 at.% Ga), Sm5Ga3 (13.3 at.% Sn), Sm5Sn3 (4 at.% Ga), and SmGa (3 at.% Sn) were observed. Three ternary compounds were found at 600C: Sm3Ga0.80-2.48Sn4.20-2.52 (ternary variant of the structure type Pu3Pd5, Pearson symbol oS32, space group Cmcm, a = 9.97522(18)-9.89433(18), b = 8.02642(16)-7.87246(16), c = 10.23304(19)-9.91703(19) Å), Sm11Ga2.30Sn7.70 (ternary variant of the structure type Ho11Ge10, tI84, I4/mmm, a = 11.5876(4), c = 17.3089(5) Å), and Sm5Ga0.76Sn2.24 (structure type Nb5SiSn2, ternary variant of W5Si3, tI32, I4/mcm, a = 12.1881(14), c = 6.0919(7) Å). The ternary phases are characterized by partial ordering of the Ga and Sn atoms.

 

Isothermal section of the phase diagram of the ternary system SmGaSn at 600C

 

Keywords

Samarium / Gallium / Tin / Phase diagram / X-ray powder diffraction / Crystal structure / Solid solution