Structural, spectral characterization and electron paramagnetic resonance studies of Ni2+ ions in various compounds: KZnF3, CdCl2, CdBr2 and CsMgI3

Abstract

The electron paramagnetic resonance (EPR) parameters (zero-field splitting D, and g-factors g ∥, g ⊥) for d 8 Ni2+ ions in tetragonal ligand fields KZnF3 : Ni2+ or in trigonal ligand fields CdCl2(CdBr2 and CsMgI3) : Ni2+ complexes have been systematically studied on the basis of the 45 × 45 complete energy matrices. The local structural distortion parameters of the crystals obtained are ΔR 1 = 0.0355 Å, ΔR 2 = 0.0296 Å for KZnF3 : Ni2+, ΔR = −0.1730 Å, Δθ = −1.5695○ for CdCl2 : Ni2+, Å, Δθ = −2.6236○ for CdBr2 : Ni2+ and ΔR = −0.0267 Å, Δθ = −1.8967○ for CsMgI3 : Ni2+. The calculated results show that the local structures exhibit elongation distortion for KZnF3 : Ni2+ and compression distortions for Ni2+ : CdCl2 (CdBr2 and CsMgI3) systems. Further, the relationships between ZFS parameter D and structural parameters (θ, R) are studied and the influence of the orbit reduction factor k on g-factors (Δg, g) are discussed.