Paramagnetic resonance of platinum ions in PbTiO3 single crystals

Abstract
Optical excitation of trivalent platinum (5d7, t6e) ions in lead titanate single crystals have been observed for the first time by electron paramagnetic resonance (EPR). The g and hyperfine coupling A tensors were found to be axial: g=1.938, g=2.478, A=0.0164 cm−1, and A=0.0324 cm−1. Analysis of the EPR spectra using crystal field theory indicates that the Pt+3 ions are in tetragonally distorted (elongated) octahedral sites, strongly suggesting that they substitute for the central Ti+4 ions in the perovskite lattice.