Paramagnetic defects in Li2ZrO3 produced by γ-ray irradiation at 77K and subsequent thermal annealing were studied by using electron spin resonance. The signal at 77K had an anisotropic g-factor of orthorhombic symmetry, g1 = 2.0391, g2 = 2.0329 and g3 = 2.0044, and was attributed to a hole center O-. An Al-related hole center was observed by annealing at 180 to 230K. The signal shape could be explained in terms of the hyperfine splittings caused by a neighboring nuclear spin I = 5/2 of 27Al3+ impurity. The third signal, at 230 to 380K, was attributed to a hole-trapped center of unknown origin from the g-factor with an orthorhombic symmetry, g1 = 2.027, g2 = 2.012 and g3 = 2.0061. The fourth signal, observed by annealing above 240K, was an unknown electron center with an isotropic symmetry g = 2.0020 and linewidth of 1.55mT.

Electron Spin Resonance Study of Defects in Lithium Zirconate (Li2ZrO3) Produced by 77K γ-Irradiation. T.Teshima, M.Ikeya: Japanese Journal of Applied Physics - 1, 2002, 41[2A], 685-9