Synthesis, structural and magnetic studies of the double perovskites Ba2CeMO6 (M = Ta, Nb)

Two Ce(3+) containing double perovskites Ba(2)CeMO(6) (M = Nb and Ta) have been prepared through the use of mildly reducing conditions, and the Ce valence state has been shown to be +3 through Ce L-edge X-ray absorption measurements. Both oxides adopt a monoclinic structure in I2/m at room temperature and undergo two phase transitions upon heating, a discontinuous I2/m -> R (3) over bar and a continuous R (3) over bar -> Fm (3) over barm transition. Analysis of the first order I2/m -> R (3) over bar transitions is impeded by the complex peak shapes and diffuse scattering evident in the synchrotron powder diffraction data because of domain wall effects. © 2012, American Chemical Society.

Keywords

Perovskite, Cerium, Phase transformations, Neutron diffraction, X-ray lasers, Crystals

Citation

Zhou, Q. D., Blanchard, P., Kennedy, B. J., Reynolds, E., Zhang, Z., Miiller, W., Aitken, J. B., Avdeev, M., Jang, L. Y., & Kimpton, J. A. (2012). Synthesis, structural and magnetic studies of the double perovskites Ba2CeMO6 (M = Ta, Nb). Chemistry of Materials, 24(15), 2978-2986. doi:10.1021/cm301278a