Simultaneous changes of nuclear and magnetic structures across the morphotropic phase boundary in (1-x)BiFeO3-xPbTiO3

We present here the results of a powder neutron diffraction study on the (1-x) BiFeO3-xPbTiO(3) (BF-xPT) system, which reveal an abrupt change in magnetic structure from a noncollinear antiferromagnetic one to a collinear G-type antiferromagnetic as the nuclear structure of the ferroelectric phase changes from monoclinic in Cc space group for x <= 0.27 to tetragonal in P4mm space group for x >= 0.31 across the morphotropic phase boundary (MPB). This reflects the multiferroic character of the MPB in the BF-xPT system. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3533665]