Figure 1. Crystal structure.

(a) High-resolution XRD pattern and Rietveld refinement for the Bi_0.68Pb_0.32Fe_0.655Mn_0.025Ti_0.32O₃ powder sample, at room temperature, indicating phase coexistence between polymorphs with monoclinic Cc and tetragonal P4mm symmetries. Y_Obs and Y_Cal refer to the measured and calculated intensities, respectively. The refined profiles using the (b,c) Cc and (d,e) R3c symmetries across the (200)_p and (103)_p reflections (referring to pseudocubic indices) are shown to illustrate the better agreement of the Cc phase.