Raman spectra and phase composition of MnGeO3 crystals

Abstract

MnGeO3 single-crystal samples have been synthesized by optical zonal melting and spontaneous crystallization. X-ray crystal analysis showed the first sample to be a two-phase one with phase ratio as follows: 17% – monoclinic C2/c, and 83%– orthorhombic Pbca; the phase ratio of the second sample was unknown. Raman spectra have been produced for these samples. Lattice dynamics has been simulated and polarization dependencies of lines’ intensities have been analyzed to interpret experimental Raman spectra and to attribute lines to the spectra of monoclinic and orthorhombic phases.