Magnetization Measurements and 55Mn NMR Studies of LaNi0.5Mn0.5O3

Magnetization measurements and 55 Mn NMR study of a system with the nominal formula LaNi 1- x Mn x O 3 (0.0 ≤ x ≤0.5) were made. It was found that materials with 0.03 ≤ x ≤0.5 are mixtures of a Pauli paramagnet LaNiO 3 and a ferromagnet LaNi 0.5 Mn 0.5 O 3 . The Curie temperature of LaNi 0.5 Mn 0.5 O 3 was found to be 275 K. In this material, strong 55 Mn NMR signals associated with Mn 4+ were observed. The observed hyperfine magnetic fields are about -260 kOe, which is considerably smaller than the ones observed for the Mn 4+ ions in other oxides. This smallness of the value seems to be due to the supertransferred hyperfine magnetic fields from the neighboring Ni 2+ ions.