Please use this identifier to cite or link to this item:
Title: Crystal structures and phase transition in (Sr0.8Ce0.2)(Mn(1-y)Coy)O-3 (y=0 and 0.2): the influence of Jahn-Teller distortion
Authors: Zhang, Z
Howard, CJ
Kennedy, BJ
Matsuda, M
Miyake, M
Keywords: Crystal structure
Phase transformations
Jahn-Teller effect
Neutron diffraction
Electric conductivity
Temperature range
Issue Date: 25-Mar-2009
Publisher: Institute of Physics
Citation: Zhang, Z., Howard, C. J., Kennedy, B. J., Matsuda, M., & Miyake, M. (2009). Crystal structures and phase transition in (sr0.8ce0.2)(mn(1-y)coy)o-3 (y=0 and 0.2): the influence of Jahn-Teller distortion. Journal of Physics-Condensed Matter, 21(12), 124218. doi:10.1088/0953-8984/21/12/124218
Abstract: We have studied the crystal structures of (Sr0.8Ce0.2)(Mn1-yCoy)O-3 (y = 0 and 0.2) using neutron diffraction. Both (Sr0.8Ce0.2)MnO3 and (Sr0.8Ce0.2)(Mn0.8Co0.2)O-3 have a tetragonal structure in space group I4/mcm at room temperature, and the octahedral tilt angle around the c-axis is nearly the same. The only significant difference is the shape of the Mn(Co)O-6 octahedron: it is elongated in (Sr0.8Ce0.2)MnO3 due to the cooperative Jahn-Teller (JT) effect, but essentially regular in (Sr0.8Ce0.2)(Mn0.8Co0.2) O3 due to the absence of JT-active Mn3+ ions. With increasing temperature, both compounds undergo a continuous phase transition at around 400°C to a cubic structure in Pm (3) over barm, with no indication of a distinct transition in (Sr0.8Ce0.2) MnO3 from the removal of the static JT distortion. In addition, the temperature dependence of the octahedral tilt angle is very similar in the two samples, implying that the JT distortion has minimal effect on the octahedral tilting and the phase transition to cubic. X-ray absorption near-edge structure (XANES) analysis indicates that the Ce oxidation state is predominantly 4+ in both samples. The electrical conductivity is higher in (Sr0.8Ce0.2)MnO3 than in (Sr0.8Ce0.2)(Mn0.8Co0.2)O-3 in the temperature range studied (100-900°C). © 2009, Institute of Physics
Gov't Doc #: 1373
ISSN: 0953-8984
Appears in Collections:Journal Articles

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.