The local structures of rhombohedral, monoclinic, and tetragonal phases across the morphotropic phase boundary (MPB) of Pb͑Zr 1−x Ti x ͒O 3 are discussed in terms of the progression from short-range to long-range and back to short-range structural order. It is shown that, provided one considers the structures on a suitably small length scale, all three phases can be considered to be monoclinic at the local level and that there need not be any discrete phase boundaries across the MPB. Electron diffraction experiments showing significant variations in diffuse streaking, illustrating the progression from short-range to long-range order, are presented in support of this model. It is suggested that it is the change in the range of structural order that plays the most important role in the increase in electrical and electromechanical properties around the MPB.

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In this study, we present a new approach toward titanium oxide nanowires. In this approach, the growth formation of the wires sets in at a temperature as low as 40 degrees C under ambient pressure. Moreover, we provide evidence that nanowires with distinctive TiO2-anatase and TiO2-B structures can be directly produced without further thermal treatment using controlled reaction conditions.

In this study, free standing crystalline ZnSe nanorings and nanowires have been fabricated on Au coated Si substrates by simple thermal evaporation of ZnSe powders. Ring-or wirelike morphology can be achieved in a controllable manner by using different reactor pressures during growth, while all the other conditions remain the same. Our results show that the ZnSe nanorings are wurtzite phase instead of the zinc-blende phase, observed in typical one-dimensional ZnSe nanostructures. The growth mechanism of the nanorings has been discussed, and the cathodoluminescence of the nanorings has been described.