Crystal structure and its stability in CeCuAl3 single crystal

• High-temperature properties of CeCuAl3 single crystal.
• CeCuAl3 compound crystallizes in tetragonal BaNiSn3-type structure.
• Structural phase transition at 300 °C preserve the BaNiSn3 structure.

We present the crystal structure investigation of CeCuAl3 compound. Our X-ray diffraction study confirms unambiguously BaNiSn3-type structure as the crystal structure of CeCuAl3 in whole temperature range. Moreover, phase transition around 300 °C was found by our high-temperature powder X-ray diffraction measurement. This transition preserves BaNiSn3-type structure, only structural parameters change during the transition. The study is provided on single crystalline and polycrystalline samples as well as on La counterpart to compare mainly high-temperature behavior of these compounds.