Single-crystal magnetic properties of lanthanide complexes. Part V. Hexakis(antipyrine)erbium(III) tri-iodide

Abstract

The principal magnetic moments of crystals of hexakis(antipyrine)erbium(III) tri-iodide (antipyrine is 2,3-dimethyl-1-phenyl-Δ³-pyrazolin-5-one) have been measured in the temperature range 300–80 K. These are interpreted within a free-ion f^11,4/_15/2+⁴/_13/2+⁴/_11/2 basis, perturbed by spin–orbit coupling and a crystal field of D_3d symmetry. Values related to the coefficient of the second-order potential and for the fourth- and sixth-order radial parameters [A₂⁰〈r²〉, ρ₄ and ρ₆ respectively] have been determined. The effects of intermediate coupling on the ground-state eigenvalues are included but shown to affect the magnetic moments only slightly.