Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10713937 | Physica B: Condensed Matter | 2012 | 5 Pages |
Abstract
The crystal structure evolution of the Sr2GdRuO6 complex perovskite at high-temperature has been investigated over a wide temperature range between 298 Kâ¤Tâ¤1273 K. Powder X-ray diffraction measurements at room temperature and Rietveld analysis show that this compounds crystallizes in a monoclinic perovskite-type structure with P21/n (#14) space group and the 1:1 ordered arrangement of Ru5+ and Gd3+ cations over the six-coordinate M sites, with lattice parameters a=5.81032(8) Ã
, b=5.82341(4)Â Ã
, c=8.21939(7)Â Ã
, V=278.11(6)Â Ã
3 and angle β=90.311(2)o. The high-temperature analysis shows that this material suffers two-phase transitions. At 373 K it adopts a monoclinic perovskite structure with I2/m space group, and lattice parameters a=5.81383(2) Ã
, b=5.82526(4)Â Ã
, c=8.22486(1)Â Ã
, V=278.56(2)Â Ã
3 and angle β=90.28(2)o. Above of 773 K, it suffers a phase transition from monoclinic I2/m to tetragonal I4/m, with lattice parameters a=5.84779(1) Ã
, c=8.27261(1)Â Ã
, V=282.89(5)Â Ã
3 and angle β=90.02(9)o. The high-temperature phase transition from monoclinic I2/m to tetragonal I4/m is characterized by strongly anisotropic displacements of the anions.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
C.A. Triana, L.T. Corredor, D.A. LandÃnez Téllez, J. Roa-Rojas,