MN55 NUCLEAR MAGNETIC RESONANCE OF MN3+ ION LOCATED AT B-SITE IN MANGANESE FERRITE SINGLE CRYSTAL - ANISOTROPIC HYPERFINE FIELD DUE TO LOCAL JAHN-TELLER DISTORTION

Nuclear Magnetic Resonance (NMR) of Mn55associated with the Mn3+ion at the octahedral site in its magnetically ordered state has been studied on manganese ferrite of cubic phase. Using a single crystal sample, the large anisotropic hyperfine field of +115 kOe, in addition to the isotropic hyperfine field of -360 kOe, has been observed, which is characteristic of the Mn3+ion at the octahedral site with the Jahn-Teller distortion. These two values of the hyperfine fields are consistent both with the theoretically calculated values and with the data of the hyperfine coupling constants of the paramagnetic Mn3+ion. It was found that the ground state of the Mn3+ion at the octahedral site was of B 1 g type and that the directions of tetragonal axes (Jahn-Teller axes) were three equivalent<100> axes. In connection with the unsuccessful observation of the quadrupole-splitted lines, which are also characteristic of NMR in the MN3+ion, the effects and the origins of the lower symmetry crystalline fields are discussed. © 1969, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.