Effect of Monoclinic Symmetry on the EPR Spectra of Gd³⁺‐Doped Hydrated Single Crystals of Rare‐Earth Trichlorides

Authors:

• S.K. Misra,
• Czesław Zygmunt Rudowicz

Abstract

Room‐temperature X‐band EPR data for Gd³⁺‐doped isostructural rare‐earth trichloride hexahydrates are analyzed using a rigorous least‐squares‐fitting procedure. Discussion of the three forms of spin Hamiltonian corresponding to the orientations of the two‐fold monoclinic symmetry axis C₂ parallel to the magnetic axes X, Y, and Z is provided. It is found that for, C₂ ∥ Y, a significantly lower value of χ², representing the goodness of fit, is obtained. A discussion of the determination of degree of monoclinicity, as revealed by the spin Hamiltonian parameters, is provided. Systematics of the spin Hamiltonian parameters b 20 and b 22, as functions of the host–ion radius, are also studied. Copyright © 1988 WILEY‐VCH Verlag GmbH & Co. KGaA