Far infrared reflectance of sintered Zn2TiO4

Zinc-titanate ceramics were obtained by initial mechanical activation in a high-energy planetary mill for 15 min followed by sintering at temperatures 900-1100°C for 2 h. Room temperature far infrared reflectivity spectra for all samples were measured in the range 100-1200 cm-1. The same ionic oscillators were present in the measured spectra, but their intensities increased with the sintering temperature in correlation with the increase in sample density and microstructure changes. Optical parameters were determined for seven oscillators belonging to the spinel structure using the four-parameter model of coupled oscillators. Born effective charges were calculated from the transversal/longitudinal splitting. © 2008 Springer Science+Business Media, LLC.