Ceramics in the (BiMnO 3 ) x –(PbTiO 3 ) 1− x series were fabricated with compositions in the range . A macroscopically pseudocubic structure was observed for compositions x >0.4 while at x <0.4 the structure is tetragonal. The presence of a pseudocubic structure is attributed to frustration between different preferred environments of cations, leading to an absence of long-range ordered polar ionic displacements. Microstructures similar to those of relaxors were observed at x = 0.4 and evidence of incommensurate ordering of antiparallel cation displacements was found at compositions . Permittivity measurements for x = 0.3 and 0.4 revealed diffuse frequency-dependent maxima between 100 and 300 °C. In addition, compositions with exhibited a sharp peak at higher temperature. The broad peaks are considered to arise from different time constants attributed to the grain interiors and boundaries for x = 0.3 and 0.4 whereas the sharp peak is interpreted as the Curie temperature of a tetragonal to cubic phase transition.
No takes yet. Share an insight, caveat, or question.
Woodward et al. (2004) studied this question.
Synapse has enriched 2 closely related papers on similar clinical questions. Consider them for comparative context: