Crystal-field-induced magnetostrictions in the spin reorientation process of Nd${}_2$Fe${}_{14}$B-type compounds

Abstract

Volume expansion $\Delta V/V$ associated with the spin reorientation process of Nd${}_2$Fe${}_{14}$B-type compounds has been investigated in terms of simple crystalline-electric-field (CEF) model. In this system, $\Delta V/V$ is shown to be a direct measure of second order CEF energy. Calculated anomalies in $\Delta V/V$ associated with the first-order magnetization process of Nd${}_2$Fe${}_{14}$B are presented, which well reproduced the observations.

2 pages, 2 figures, to appear in J. Magn. Magn. Mater