The magnetic structures of LaTiO3 and CeTiO3

The basic features of the magnetic structures of LaTiO3 and CeTiO3 were determined by powder neutron diffraction. LaTiO3 (TN = 125 K) is a type G antiferromagnet with a moment on Ti (III) of 0.45(5)μB at 10 K. As bulk magnetic measurements indicate a weak ferromagnetic moment, a GzFx or GxFz configuration is implied. CeTiO3 (TN) = 116 K) shows more complex behaviour. At 81 K only G and F type reflections are observed. The most consistent interpretation is to assign G-type configuration to Ti(III) and an induced Fz on Ce(III). Moments are 0.36μB on Ti(III) and 0.4(1)μB on Ce(III). It is also possible to assign both G and F components to Ti(III). This demands a “canting angle” of 34° to explain the F moment. Below 80 K a C-type component develops. A model assuming a GzFx configuration for Ti(III) and a CyFx configuration for Ce(III) provides a good fit to the data. This assignment is consistent with Bertaut's symmetry considerations. Other models which violate Bertaut's rules also fit the data.