%0 Journal Article %1 WOS:000270692700009 %A Lima, J A %A Paraguassu, W %A Freire, P T C %A Filho, A G Souza %A Paschoal, C W A %A Filho, J Mendes %A Zanin, A L %A Lente, M H %A Garcia, D %A Eiras, J A %C 111 RIVER ST, HOBOKEN 07030-5774, NJ USA %D 2009 %I WILEY %J JOURNAL OF RAMAN SPECTROSCOPY %K PMN; dynamics} ferroelectrics; lattice relaxors; scattering; {Raman %N 9 %P 1144-1149 %R 10.1002/jrs.2247 %T Lattice dynamics and low-temperature Raman spectroscopy studies of PMN-PT relaxors %V 40 %X In this work we present a Raman scattering study of a specific region of the morphotropic phase boundary (MPB) of the Pb(Mg1/3Nb2/3)O-3(1-x) (PbTiO3)(x) relaxor system. We performed low-temperature measurement for the x = 0.4 composition in the 20-300 K temperature range, and a detailed analysis of Raman spectra of x = 0.4 and x = 0.37 compositions at 180 K. The analysis of Raman spectra indicates a structural phase transition at around 170 K for x = 0.4. The comparison of Raman data from x = 0.4 and x = 0.37 compositions suggests different phases for these samples at 180 K. These results are in accordance with the tetragonal to monoclinic structural phase transition observed in the PMN-PT MPB and contribute to improve the knowledge of the MPB of this solid solution. Additionally, we have performed the lattice dynamics phonon calculation of the (1 - x) PMN-xPT relaxor in order to best understand its complex Raman spectral properties. The normal mode analyses (at q similar to 0) were performed by considering tetragonal symmetry for the (1 - x) PMN-xPT system and using the rigid ion model and mean field approximation. Our calculated wavenumber values are in good agreement with experimental and calculated results reported for PbTiO3 thus providing a reliable assignment of the various Raman modes. The low wavenumber modes are interpreted as arising from a lifting of the degeneracy of the vibrational modes related to Mg, Nb and Ti sites. Copyright (C) 2009 John Wiley & Sons, Ltd.

@article{WOS:000270692700009, abstract = {In this work we present a Raman scattering study of a specific region of the morphotropic phase boundary (MPB) of the [Pb(Mg1/3Nb2/3)O-3](1-x) (PbTiO3)(x) relaxor system. We performed low-temperature measurement for the x = 0.4 composition in the 20-300 K temperature range, and a detailed analysis of Raman spectra of x = 0.4 and x = 0.37 compositions at 180 K. The analysis of Raman spectra indicates a structural phase transition at around 170 K for x = 0.4. The comparison of Raman data from x = 0.4 and x = 0.37 compositions suggests different phases for these samples at 180 K. These results are in accordance with the tetragonal to monoclinic structural phase transition observed in the PMN-PT MPB and contribute to improve the knowledge of the MPB of this solid solution. Additionally, we have performed the lattice dynamics phonon calculation of the (1 - x) PMN-xPT relaxor in order to best understand its complex Raman spectral properties. The normal mode analyses (at q similar to 0) were performed by considering tetragonal symmetry for the (1 - x) PMN-xPT system and using the rigid ion model and mean field approximation. Our calculated wavenumber values are in good agreement with experimental and calculated results reported for PbTiO3 thus providing a reliable assignment of the various Raman modes. The low wavenumber modes are interpreted as arising from a lifting of the degeneracy of the vibrational modes related to Mg, Nb and Ti sites. Copyright (C) 2009 John Wiley & Sons, Ltd.}, added-at = {2022-05-23T20:00:14.000+0200}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, author = {Lima, J A and Paraguassu, W and Freire, P T C and Filho, A G Souza and Paschoal, C W A and Filho, J Mendes and Zanin, A L and Lente, M H and Garcia, D and Eiras, J A}, biburl = {https://www.bibsonomy.org/bibtex/222aec81744488e58bf4dffb5ac8991e5/ppgfis_ufc_br}, doi = {10.1002/jrs.2247}, interhash = {33d6dc4a6b0381fa6cb64075b82f7c1b}, intrahash = {22aec81744488e58bf4dffb5ac8991e5}, issn = {0377-0486}, journal = {JOURNAL OF RAMAN SPECTROSCOPY}, keywords = {PMN; dynamics} ferroelectrics; lattice relaxors; scattering; {Raman}, number = 9, pages = {1144-1149}, publisher = {WILEY}, pubstate = {published}, timestamp = {2022-05-23T20:00:14.000+0200}, title = {Lattice dynamics and low-temperature Raman spectroscopy studies of PMN-PT relaxors}, tppubtype = {article}, volume = 40, year = 2009 }