Fyzikální ústav Akademie věd ČR

X-ray powder diffractometer Bruker D8 (CuKα radiation, SOL-X energy dispersive detector) is used to determine:

• Phase compositions
• Lattice parameters
• Crystal structure
• Crystallite (grain) size
• Preferred orientation (texture)

X-ray diffraction patterns are analyzed with the Rietveld method using the FullProf and JANA programs. The structures of detected phases are collected with the help of ICSD.

Thompson-Cox-Hastings pseudo-Voigt profile is used to resolve instrumental, strain and size contributions to peak broadening. Instrumental resolution is determined by measuring strain-free tungsten powder with grain size 9.4 µm.

Kalvados software is used for working with powder diffraction data and crystal structure files.

The temperature dependent structural characterization over the range 90-1200 K is realized using MRI TC-wide range temperature chamber. The measurements can be performed under ambient atmosphere, vacuum or flowing gas. Two scans are typically measured for each temperature and the measured intensities are compared in order to check the thermal stability and reproducibility of the sample structure.