Structural characterisation of the perovskite series Sr{sub x}Ca{sub 1-x-y}Nd{sub y}MnO{sub 3}: Influence of the Jahn-Teller effect

Journal Article · Thu Oct 15 00:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.07.041· OSTI ID:21372358

Saines, Paul J; Ting, Jimmy; Qingdi, Zhou ^[1]; Kimpton, Justin A ^[2]

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1. School of Chemistry, University of Sydney, New South Wales 2006 (Australia)
2. Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168 (Australia)

The crystal structures of the perovskite manganites Sr{sub x}Ca{sub 1-x-y}Nd{sub y}MnO{sub 3} with y=0.1 or 0.2 have been investigated using synchrotron X-ray powder diffraction. At room temperature the structures change from Pm3-barmreversibleI4/mcmreversiblePbnm depending on the cation distribution, the different structures exhibiting different tilts of the MnO{sub 6} octahedra. High temperature diffraction measurements demonstrate the presence of, an apparently continuous, isosymmetric I4/mcm to I4/mcm phase transition associated with the removal of long range orbital ordering. Heating the manganites to still higher temperatures results in a continuous transition to the cubic Pm3-barm structure. A feature of such transitions is the continuous evolution of the octahedral tilt angle through the I4/mcm to I4/mcm phase transition. The orthorhombic structures do not exhibit orbital ordering and although a first order transition to the tetragonal structure is observed in Sr{sub 0.4}Ca{sub 0.5}Nd{sub 0.1}MnO{sub 3}, this high temperature tetragonal structure does not exhibit orbital ordering. - Graphical abstract: Structural studies of oxides of the type Sr{sub x}Ca{sub 1-x-y}Nd{sub y}MnO{sub 3} series illustrate the continuous removal of the octahedral tilting, despite the loss of orbital ordering.

• OSTI ID: 21372358
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 10; Other Information: DOI: 10.1016/j.jssc.2009.07.041; PII: S0022-4596(09)00344-2; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CALCIUM COMPOUNDS
CATIONS
HEATING
JAHN-TELLER EFFECT
MANGANESE COMPOUNDS
NEODYMIUM COMPOUNDS
ORTHORHOMBIC LATTICES
OXIDES
PEROVSKITE
PHASE TRANSFORMATIONS
STRONTIUM COMPOUNDS
TEMPERATURE RANGE 0273-0400 K
TETRAGONAL LATTICES
X-RAY DIFFRACTION
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
CHARGED PARTICLES
COHERENT SCATTERING
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIFFRACTION
IONS
MINERALS
OXIDE MINERALS
OXYGEN COMPOUNDS
PEROVSKITES
RARE EARTH COMPOUNDS
SCATTERING
TEMPERATURE RANGE
TRANSITION ELEMENT COMPOUNDS