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 04:00:00 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, Journal Name: Journal of Solid State Chemistry Journal Issue: 10 Vol. 182; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

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