Local Lattice Distortion near Co2+ in SrLaAlO4 Crystal

Abstract The local tetragonal distortion in the vicinity of substitutional Co 2+ impurities in SrLaAlO 4 crystal is studied by fitting the calculated EPR parameters g\\, g⟂, A\\ and A⟂ to the observed values. The result shows that the local distortion is mainly due to the elongation of metal-ligand distance R± perpendicular to the C 4 axis. This point is consistent with the expectation based on the consideration of ionic radius sum. This smaller tetragonal distortion of the oxygen octahedron surrounding the Co 2+ impurity than that in the host crystal is supported by the result obtained in Cr 3+ -doped SrLaAlO 4 crystal. -P a cs: 61.70Rj; 76.30Fc; 71.70Ch