Raman spectroscopy of (Fe,Li)-doped delafossite oxide CuCrO2

In this paper we investigated the vibrational properties of (Fe,Li)-doped delafossite oxide CuCrO2 by means of Raman experiments. The measurements were carried out at ambient temperature and pressure and on ab- and a(b)c-plane of a single grain. The samples were prepared using self-combustion urea nitrate process and the structure of all samples was checked using X-ray diffraction. All peaks were indexed as arising from CuCrO2 delafossite with space group R-3 m. Active phonon modes with A(1g) and E-g symmetries were identified as well as the presence of one additional line that could not be associated with inhomogeneities at microscopic level. The frequencies of the A(1g) and E-g modes were also observed to be independent upon Fe and Li doping, but not the corresponding scattering intensities.