Magnetic anisotropy in nickel complexes as determined by combined magnetic susceptibility/magnetization/theoreticaI studies

The zero-field splitting in nickel(II) complexes was modeled by considering all relevant operators (electron repulsion, crystal-field, spin-orbit coupling, orbital-Zeeman, and spin-Zeeman) in the complete basis set spanned by d-atomic terms. D-values between weak and strong crystal field limits were evaluated from the crystal-field multiplets as well as using the spin Hamiltonian formalism. Importance of the anisotropic orbital reduction factors is discussed and exemplified by D/hc = -22 cm(-1) as subtracted from magnetic data for [Ni(imidazole)(4)(acetate)(2)] complex. (C) 2004 Elsevier B.V. All rights reserved.