Absorption, Fluorescence, and Magnetic Properties of Gadolinium Chloride (GdCl_3·6H_2O)†

Abstract

A study of the Zeeman effect of absorption lines of GdCl3·6H2O and its dependence on the orientation of the crystal has given the constants for the magnetic ellipsoids for the ground state and 11 excited states. Evidence is presented for identifying the first three absorption groups as transitions from 8S to 6P7/2, 6P5/2, and 6I7/2. The magnetic observations were made at 77°K, 4.2°K, and 1.7°K and field-free spectra also taken at 195°K and 273°K. Very strong fluorescence is observed from the lowest excited state to the ground state.The magnetic axes are approximately but not exactly the same for all observed states. The direction of maximum susceptibility is not that of the twofold crystal axis but perpendicular to it. There are small but definite deviations from isotropic magnetic behavior for the ground state.