Vibrational spectroscopy study of the lattice defects in CaZrO3 ceramics

CaZrO3 materials were prepared by a solid state reaction. The samples were pre-calcined and sintered at 1673 K for 6 h. They were then analysed using Fourier Transform-Infrared spectroscopy. Microwave dielectric function (ε=ε′+iε″) were determined by Kramers–Kronig analysis. The reflectance spectra were then adjusted using the classical dispersion equations taking into account the LO/TO (longitudinal/transverse optic) mode splitting. The most unfavourable mode in terms of dissipation was found to be the first one (ωT=106.9 cm−1). A simple adjustment of this mode transverse optic damping constant was then carried out to fit the reflectance spectra of slightly non-stoichiometric CaZrO3 materials. This procedure was conclusive except for excessive Zr non-stoichiometry (extrapolated to >2.78%).