Magnetism and charge ordering in Fe3O2BO3 ludwigite

Features of the magnetic and charge ordering of the Fe3O2BO3 ludwigite have been studied using Mossbauer spectroscopy in the range of 4 K < T < 120 K. From the temperature dependence of the magnetic hyperfine fields (B-hf), a ssociated to four different iron sites, three magnetic transitions, at 112, 73 and 40 K, can be distinguished in agreement with previous magnetization measurements. In the temperature region where a weak ferromagnetism appear s, the B-hf of some Fe sites show two different values related with differe nt canting angles. (C) 2001 Elsevier Science B.V. All rights reserved.