Magnetic properties of CsNiCl3 and RbNiCl3

Abstract
The magnetic moment and susceptibility of the linear‐chain antiferromagnets CsNiCl3 and RbNiCl3 have been studied up to fields of 60 kG from 1.1 K to beyond their respective Néel temperatures. In both compounds clear evidence for a spin‐flop transition near 20 kG has been obtained with the applied field parallel to the c‐axis. Details of the magnetic phase diagram for CsNiCl3 have been clarified, particularly with respect to the spin reorientation which occurs near 4.4 K at low fields. No evidence has been obtained for the existence of a corresponding reorientation in RbNiCl3.