Guarany, C. A.Pelaio, LHZAraujo, E. B.Yukimitu, K.Moraes, João Carlos Silos [UNESP]Eiras, J. A.2014-05-202014-05-202003-07-16Journal of Physics-condensed Matter. Bristol: Iop Publishing Ltd, v. 15, n. 27, p. 4851-4857, 2003.0953-8984http://hdl.handle.net/11449/9999Recently, the observation of a new monoclinic phase in the PbZr1-xTixO3 (PZT) system in the vicinity of the morphotropic phase boundary was reported. Investigations of this new phase were reported using different techniques such as high-resolution synchrotron x-ray powder diffraction and Raman spectroscopy. In this work, the monoclinic --> tetragonal phase transition in PbZr0.50Ti0.50O3 ceramics was studied using infrared spectroscopy between 1000 and 400 cm(-1). The four possible nu(1)-stretching modes (Ti-O and Zr-O stretch) in the BO6 octahedron in the ABO(3) structure of PZT in this region were monitored as a function of temperature. The lower-frequency mode nu(1)-(Zr-O) remains practically unaltered, while both intermediate nu(1)-(Ti-O) modes decrease linearly as temperature increases from 89 to 263 K. In contrast, the higher-frequency nu(1)-(Ti-O) and nu(1)-(Zr-O) modes present anomalous behaviour around 178 K. The singularity observed at this mode was associated with the monoclinic --> tetragonal phase transition in PbZr0.50Ti0.50O3 ceramics.4851-4857engArtigo10.1088/0953-8984/15/27/316WOS:000184600600020Acesso restrito67259822284020548507741729691974