TDPAC measurements in pure and Fe-doped In2O3

Measurements of the electric quadrupole interactions were used to characterize pure and Fe-doped In2O3 samples using perturbed γ-γ angular correlation (PAC) technique with 111In-111Cd radioactive probe. The samples of pure as well as 1 % and 5 % Fe-doped In2O3 were prepared by sol–gel method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray spectroscopy (EDS). The PAC measurements were carried out with a conventional fast-slow coincidence set-up using four BaF2 detectors as a function of temperature from 295 K to 1073 K. The powder XRD spectra analyzed with Rietveld method as well as SEM and EDS results showed that Fe-doped samples are homogeneous without any secondary iron oxide phases. The PAC spectra of pure and 1 % Fe-doped In2O3 show well-known characteristic quadrupole frequencies for the two non-equivalent sites in the bixbyte structure. The hyperfine parameters in these cases change little with temperature. For the 5 % Fe-doped sample however the PAC spectra changed significantly and a third frequency with large η appears.