The Orbit?Lattice Interaction for Lanthanide Ions. II. Strain and Relaxation Time Predictions for Cubic Systems

Abstract

An analysis of dynamic crystal field data for cubic systems is carried out in order to assess the possible usefulness of the superposition model in understanding the results of lattice strain and spin-lattice relaxation experiments. The data used in this work are the electron paramagnetic resonance (EPR) results for strained cubic crystals obtained by Buisson, Baker and their coworkers, and the spinlattice relaxation results obtained by Buisson, Stapleton and their coworkers. A method of generalizing the superposition model to take into account long range electrostatic contributions without introducing additional unknown parameters is proposed, and shown to give consistent results. It is concluded that differences between bulk and local strains must be taken into account in any model of the dynamic crystal field, if it is to achieve success.