[en] The full phonon dispersion relations of lead titanate and lead zirconate in the cubic perovskite structure are computed using first-principles variational density-functional perturbation theory, with nb initio pseudopotentials and a plane-wave basis set. Comparison with the results previously obtained for barium titanate shows that the change of a single constituent (Ba to Pb, Ti to Zr) has profound effects on the character and dispersion of unstable modes, with significant implications for the nature of the phase transitions and the dielectric and piezoelectric responses of the compounds. Examination of the interatomic force constants in real space, obtained by a transformation which correctly treats the long-range dipolar contribution, shows that most are strikingly similar, while it is the differences in a few key interactions which produce the observed changes in the phonon dispersions. These trends suggest the possibility of the transferability of force constants to predict the lattice dynamics of perovskite solid solutions.
Disciplines :
Physics
Author, co-author :
Ghosez, Philippe ; Université de Liège - ULiège > Département de physique > Physique théorique des matériaux
Cockayne, E.
Waghmare, U. V.
Rabe, K. M.
Language :
English
Title :
Lattice dynamics of BaTiO3, PbTiO3, and PbZrO3: A comparative first-principles study
Publication date :
1999
Journal title :
Physical Review. B, Condensed Matter
ISSN :
0163-1829
eISSN :
1095-3795
Publisher :
American Institute of Physics, New York, United States - New York
M. E. Lines and A. M. Glass, Principles and Applications of Ferroelectrics and Related Materials (Clarendon Press, Oxford, 1977).
D. Vanderbilt, Curr. Opin. Solid State Mater. Sci. 2, 701 (1997).
K. M. Rabe and U. V. Waghmare, Ferroelectrics. 136, 147 (1992)
Ferroelectrics, K. M. Rabe, U. V. Waghmare, 164, 15 (1995).
N. E. Zein, Sov. Phys. Solid State. 26, 1825 (1984)
S. Baroni, P. Giannozzi, and A. Testa, Phys. Rev. Lett. 58, 1861 (1987).
X. Gonze, D. C. Allan, and M. P. Teter, Phys. Rev. Lett. 68, 3603 (1992).
R. Yu and H. Krakauer, Phys. Rev. Lett. 74, 4067 (1995).
K. M. Rabe and E. Cockayne, in First-Principles Calculations for Ferroelectrics, edited by R.E. Cohen, AIP Conf. Proc., No. 436 (AIP, Woodbury, 1998), p. 139.