Effects of the vibronic interaction on anisotropy of ESR parameters for three-coordinate complexes of univalent nickel

Vibronic interaction effects on anisotropy of ESR parameters for three-coordinate complexes of univalent nickel have been investigated. Analytical expressions in the first order of the perturbation theory were obtained for wave functions of the ground and excited doubly degenerate states having taken into account vibronic and spin-orbital interactions. Based on the assumption that the vibronic interaction prevails over spin-orbital, there were obtained the expressions for main components of the g-tensor and isotropic HFS constants with ligand cores which are consistent with experimental data for three-coordinate complexes of the composition Ni(PPh₃)₃]BF₄ and Ni(PCy₃)₃]BF₄.