  The mixed ferrite-cobaltites LnFe0.5Co0.5O3, with Ln = Eu & Dy have been
prepared by a sol-gel method and the samples have been characterized using
X-ray diffraction and electron microscopy. The magnetic investigations reveal
that both samples ordered in canted antiferromagnetic structures near room
temperature. The Dzyaloshinskii-Moriya or antisymmetric exchange interaction
induces weak ferromagnetism due to canting of the antiferromagnetically ordered
spins. In the case of Ln-Fe-Co orthoferrites, two magnetic sublattices (Ln3+-4f
and Fe3+/Co3+-3d) generally align in opposite directions and interesting
temperature dependent phenomena: e.g. uncompensated antiferromagnetic
sublattices and spin-reorientations, are observed in the system. The existence
of hysteresis at low temperature region has been explained in terms of the
strength of magnetic interactions between Fe3+ and Co3+ ions with different
A-site rare earth cations.
