Structural and magnetic studies of the lanthanide deficient perovskite Ce2/3TiO3

The lanthanide deficient perovskile Ce2/3TiO3 was synthesized in vacuum at 1400 degrees C, and the actual formula was found to be Ce2/3TiO2.95 from thermogravimetry. Its crystal structure was refined to the same structure as in La2/3TiO3, i.e, the orthorhombic double perovskite structure Pmmm having the crystallographic ordering of Ce vacancy along the c-axis. No obvious magnetic ordering was observed between 2 and 300 K in DC susceptibility-temperature (chi-T) curves. It was also suggested that the valence of the Ce ions is changed to 3 + (4f(1)) from the initial valence 4 + (4f(0)) during the sample firing in vacuum, as is the case for CeTiO3 and Ce(1-x)A(x)TiO(3) (A = Sr and Ba). Inverse susceptibility-temperature (1/chi-T) curves deviated from the Curie-Weiss law below similar to 60 K. Magnetization-field (M-H) curves exhibited almost only paramagnetic profiles down to 2 K. (C) 2000 Elsevier Science S.A. All rights reserved.