Competing Ferri- and Antiferromagnetic Phases in Geometrically   Frustrated LuFe2O4
  We present a detailed study of magnetism in LuFe2O4, combining magnetization measurements with neutron and soft x-ray diffraction. The magnetic phase diagram in the vicinity of T_N involves a metamagnetic transition separating an antiferro- and a ferrimagnetic phase. For both phases the spin structure is refined by neutron diffraction. Observed diffuse magnetic scattering far above T_N is explained in terms of near degeneracy of the magnetic phases. 
J. de Groot, K. Marty, M.D. Lumsden, A.D. Christianson, S.E. Nagler,   S. Adiga, W.J.H. Borghols, K. Schmalzl, Z. Yamani, S....
cond-mat.str-el