Structural phase transition at low temperature, corresponding to charge ordering in the CMR perovskites Ln{sub 0.5}A{sub 0.5}MnO{sub 3}

Journal Article · Thu Aug 01 00:00:00 EDT 1996 · Materials Research Bulletin

DOI:https://doi.org/10.1016/S0025-5408(96)00090-6· OSTI ID:367303

Laffez, P; Van Tendeloo, G ^[1]; Millange, F; Caignaert, V; Hervieu, M; Raveau, B ^[2]

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1. Univ. of Antwerp (Belgium)
2. Univ. of Caen (France). Lab. CRISMAT

The magneto resistive perovskites Nd{sub 0.5}Sr{sub 0.5}MnO{sub 3} and Pr{sub 0.5}Sr{sub 0.41}Ca{sub 0.09}MnO{sub 3} undergo a transition from anti ferromagnetic insulator to ferromagnetic metal as function of temperature. The room temperature phase is orthorhombic with the space group Imma and the cell parameters a {approx} {radical}2a{sub p}, b {approx} 2a{sub p}, and c {approx} {radical}2a{sub p}. A structural phase transition related to charge ordering accompanying the transition from ferromagnetic state to antiferromagnetic state has been evidenced by low temperature electron diffraction. This transition is reversible and a new superstructure, with a P-type orthorhombic cell and lattice parameters a {approx} 2{radical}a{sub p}, b {approx} 2a{sub p}, and c {approx} {radical}2a{sub p}, is formed.

• OSTI ID: 367303
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 8 Vol. 31; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AIR
ANNEALING
ANTIFERROMAGNETISM
CALCINATION
CALCIUM OXIDES
ELECTRON DIFFRACTION
ELECTRON MICROSCOPY
FERROMAGNETISM
LATTICE PARAMETERS
MAGNETIC PROPERTIES
MANGANESE OXIDES
NEODYMIUM OXIDES
ORTHORHOMBIC LATTICES
PHASE TRANSFORMATIONS
PRASEODYMIUM OXIDES
SAMPLE PREPARATION
SINTERING
STRONTIUM OXIDES
TEMPERATURE DEPENDENCE
TRANSITION TEMPERATURE