Single-crystal magnetic properties of lanthanide complexes. Part II. Tri-iodohexakis(antipyrine)cerium

Abstract

The principal magnetic moments of tri-iodohexakis(antipyrine)cerium (antipyrine is 2,3-dimethyl-1-phenyl-Δ³-pyrazolin-5-one) crystals have been determined in the temperature range 300–90 K. They are interpreted within a free-ion f¹ basis perturbed by spin–orbit coupling and a crystal-field of D_3d symmetry. The general behaviours of theoretical energy levels, magnetic moments, and e.s.r. g-values are examined as functions of second-, fourth- and sixth-order radial integrals and of geometry. Experimental susceptibilities are fitted to the model as well as previously reported g-values. The parameter values deduced and their correlations with the orbital reduction factor are discussed and compared with those from the ytterbium analogue and with elementary point-charge and point-dipole crystal-field calculations.