CORRELATION-CRYSTAL-FIELD ANALYSIS OF THE H-2(2)11/2 MULTIPLET OF ND-3+

Orthogonal correlation-crystal-field (CCF) operators for the fN configuration have been discussed in an earlier paper, with emphasis on the anomalous multiplets 3K8 of Ho3+ and 6I17/2 of Gd3+. In those cases the g3(6) operator, which is a major component of the sixth-rank spin-correlated crystal-field operator, was found to be useful. In this paper we turn our attention to the 2H(2)11/2 multiplet of Nd3+. The one-electron crystal-field parametrization consistently underestimates the splitting of this multiplet, and several possible corrections have recently been suggested in the literature. We show, by analyzing the spectrum of Nd3+ in several host crystals, that the addition of the fourth-rank orthogonal CCF operator g10A(4) to the Hamiltonian removes the anomaly. Our fits are in qualitative agreement with ab initio calculations of CCF effects for lanthanide ions. © 1990 The American Physical Society.