Interpretation of Gd3+spin-Hamiltonian parameters in garnet host crystals

Abstract

A new EPR determination of the spin-Hamiltonian parameters for Gd³⁺:YAG has been made. A direct comparison of garnet crystal-field and spin-Hamiltonian parameters, as well as the success of the superposition model analysis, enables us to eliminate the possibility of large non-linear (e.g. quadratic) crystal-field contributions to the Gd³⁺ ground-state splitting. Spin-Hamiltonian superposition model parameters are derived and an analysis of the n=2 crystal-field and spin-Hamiltonian parameters suggests that the coordinate angles derived from X-ray data are in error by about 1 degrees .