The applied field dependence of Tsub(N) for RbFeCl3

The quasi one-dimensional material RbFeCl3 has a three-dimensional ordering temperature of 2.6 K. Below this temperature the Fe2+ ions are coupled ferromagnetically in chains with spins perpendicular to the chain, c, axis. The chains couple in a triangular structure giving an overall antiferromagnet. Moessbauer spectra were taken at 4.2 K with magnetic fields applied perpendicular and parallel to the c axis. Spectra taken with the field along the c axis showed the presence of field components perpendicular to the chain indicating a transition to the ordered state and implying an increase of Tsub(N) with applied field. (orig.)