Phase equilibria in the Ce–Ti–Sb and Gd–Ti–Sb ternary systems at 600°C and the crystal structures of the Ce₂Ti₇Sb₁₂ and Gd₂Ti₁₁Sb₁₄ compounds

Chem. Met. Alloys 10 (2017) 76-92

https://doi.org/10.30970/cma10.0359

Oleksandr SENCHUK, Yaroslav TOKAYCHUK, Roman SERKIZ, Pavlo DEMCHENKO, Roman GLADYSHEVSKII

The phase equilibria in the Ce–Ti–Sb and Gd–Ti–Sb ternary systems at 600°C were established by means of X-ray powder diffraction and EDX analysis. The formation of two ternary compounds in the Ce–Ti–Sb system, Ce₃TiSb₅ (Hf₅CuSn₃ type) and Ce₂Ti₇Sb₁₂ (La₂Ti₇Sb₁₂ type), and of one ternary compound in the Gd–Ti‑Sb system, Gd₂Ti₁₁Sb₁₄ (Sm₂Ti₁₁Sb₁₄ type), was confirmed. At 600°C, seven binary compounds were found to exist in the Ti–Sb system, four in the Ce–Sb system, and four in the Gd–Sb system. No binary compounds form in the {Ce,Gd}–Ti systems. The crystal structures of the Ce₂Ti₇Sb₁₂ and Gd₂Ti₁₁Sb₁₄ compounds were refined on X-ray powder diffraction data, starting from the initial atomic parameters of the La₂Ti₇Sb₁₂ and Sm₂Ti₁₁Sb₁₄ structure types, respectively. The isothermal sections of the phase diagrams of the Ce–Ti–Sb and Gd–Ti–Sb ternary systems at 600°C were constructed in the whole concentration range.

Crystal structure of the Gd₂Ti₁₁Sb₁₄ compound.

Keywords

Cerium / Gadolinium / Titanium / Antimony / Ternary compound / Phase diagram / Crystal structure