Characterisation of LaGdO 3 by X-ray powder diffraction and raman spectroscopy

Abstract

LaGdO 3 is prepared via a reverse-strike coprecipitation method and sintered at temperatures of 1350–1450°C for 6 h. Raman spectroscopy of the sintered materials revealed profiles similar to that observed for pure B-type Gd 2O 3. Low temperature (−196°C) Raman spectra showed a total of 18 bands of a possible 21 allowed modes predicted for the monoclinic B-type mixed rare earth oxide with C2/ m space group. These bands were assigned to modes in comparison to the band assignments for Gd 2O 3 as follows; 71 ( B g ), 82 ( A g ), 98 ( B g ), 109 ( A g ), 124 ( A g ), 158 ( A g ), 182 ( A g ), 219 ( A g ), 242 ( A g ), 279 ( A g ), 315 ( B g ), 366 ( A g ), 390 ( B g ), 419 [ B g +( A g ?)], 436 ( A g ), 458 ( A g ), 560 ( A g ) and 575 ( A g ) cm −1. Powder X-ray diffraction patterns revealed a monoclinic pattern for materials sintered at all three temperatures; 1350, 1400 and 1450°C.