Electron Spin Resonance of Mn²⁺ in BaTiO₃ Single Crystal

Abstract

The paramagnetic resonance of Mn²⁺ in BaTiO₃ single crystals has been studied. The bivalent manganese ion seems to be located at the barium site in the unit cell. The “forbidden” transition lines in the hyperfine spectrum were most clearly observed in the tetragonal phase, while in the cubic phase the intensities of the forbidden lines were very small compared to those of the allowed lines. The value of the cubic field splitting parameter a in the tetragonal phase was somewhat larger than that in the cubic phase. In the tetragonal phase, the value of E has been verified to be vanishingly small in contrast to the large value of D. The hyperfine constant is anisotropic. Theoretical explanations are tried to the third-order perturbation for the splittings and the intensities of the “forbidden” lines.