OPTICAL INVESTIGATION OF METAMAGNETIC DYA1O3

We have investigated the optical absorption spectra of metamagnetic DyAlO3 (TN=3.4 °K) above and below the Néel temperature. We find that the magnetic interactions are predominantly between the ions along the crystallographic c-axis; the interaction energy between two ions is WC=- (2.9±0.6) cm-1. Additional line-shifts below 3.4 °K yield the Néel temperature. Zeeman effect studies give the magnetic moment of the groundstate as μ=(9.2 ± 0.9)μB. The direction of the magnetic moments is in the a-b plane, with angles of ± 33.5° and ± 146.5° from the b-axis. The Zeeman effect studies reveal two metamagnetic transitions (for Hext∥μ) at 7.0 and 7.3 kOe respectively. Additional susceptibility and Mössbauer measurements confirm the Néel temperature and the magnetic moment. © 1969 Springer-Verlag.