Magnetic behavior of ErCrO4 oxide

ErCrO4 has been synthesized as a single phase by the nitrate precursor method under an oxygen flow at 753 K. The structure of this compound has been refined from X-ray and neutron powder diffraction data, showing the zircon-type structure, S.G. 14(1)/amd and lattice parameters a=7.062(1) Angstrom, c=6.201(3) Angstrom. Magnetic susceptibility and magnetization measurements reveal the existence of incipient ferromagnetic interactions in the Cr5+ sublattice below 25 K. When the temperature decreases, the superexchange Er3+-O-Cr5+-O-Er3+ antiferromagnetic interactions become predominant. The estimated Neel temperature is 15 K. A metamagnetic transition has been detected at the critical field of 375 Oe. Neutron diffraction data show a three-dimensional antiferromagnetic ordering in which both Cr5+ and Er3+ sublattices are involved. Such ordering takes place with a propagation vector k=[0]. (C) 2002 Elsevier Science B.V. All rights reserved.