Raman spectroscopy investigation of lanthanide-filled and unfilled skutterudites

Raman-scattering spectra at room temperature and 10 K are studied for binar y "unfilled" and lanthanide-filled skutterudite antimonides. In the binary skuttertudites IrSb3 and RhSb3 all eight Raman-active vibrational modes hav e been identified while seven of the eight modes have been identified in Co Sb3. In the case of the filled skutterudites these vibrational modes are se nsitive to the lanthanide "filler" ions which produce a shift and large bro adening of the vibrational modes. Polarization measurements on these polycr ystalline samples were used to identify the A(g) modes. The experimental da ta are compared to theoretical predictions. [S0163-1829(99)04309-X].