American Research Journal of Materials Science

N.N. Syrbu1*, V.V. Zalamai2

 Raman scattering spectrain different geometries at temperatures 10 - 300 K and infrared vibrational spectra in polarizations E||c and E⊥c for range 50 - 4000 cm-1 at 300 K were investigated for PbGa2Se crystals. Contours of reflection spectra in polarizations E||c and E⊥c were calculated and parameters of phonons and dielectric constants were determined. Temperature dependences of Raman spectra were investigated and soft modes with different temperature dependences in intervals 80 - 150 and 150 - 370 K were discovered. A group of lines attributed to Davydovmultiplets was found out and their polarization dependences temperature changes were investigated. Effective ion charges were calculated and a polarizability of ionic charges of Pb, Ga and S in PbGa2S4 lattice was determined.