Microscopic structure of nblirelated defects in reduced undoped LiNbO³

Results of a detailed ESR investigation of Nb4+ in chemically reduced LiNbO3 are reported. The defect is assigned to antisite Nb4+ associated with a defect on a neighboring cation site, most likely VLi in crystal regions with ilmenite like Li-Nb stacking. NbLi is the most important intrinsic defect of LiNbO3