Structural changes and related effects due to charge ordering in Nd{sub 0.5}Ca{sub 0.5}MnO{sub 3}
- Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)
- Materials Research Laboratory, University of California, Santa Barbara, California 93106 (United States)
- Department of Physics, Indian Institute of Science, Bangalore 560012 (India)
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India)
Charge ordering in {ital L}{sub 1{minus}{ital x}}{ital A}{sub {ital x}}MnO{sub 3} ({ital L}=rare earth, {ital A}=Ca,Sr) depends strongly on the width of the {ital e}{sub {ital g}} band or on the average radius of the {ital A}-site cations, {l_angle}{ital r}{sub {ital A}}{r_angle}. Investigations of Nd{sub 0.5}Ca{sub 0.5}MnO{sub 3} with a small {l_angle}{ital r}{sub {ital A}}{r_angle} show evidence for a first -order transition due to charge ordering around 220 K, accompanied by a large decrease in volume (0.45{percent}). Structural data at different temperatures indicate that the distortions within the structure are a direct result of charge ordering. Valence sum calculations show the presence of two differently charged Mn atoms. Electron transport and magnetic susceptibility measurements have been carried out down to low temperatures to understand the nature of the charge-ordered state. The charge-ordered state melts on the application of a magnetic field. {copyright} {ital 1996 The American Physical Society.}
- OSTI ID:
- 397615
- Journal Information:
- Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 21 Vol. 54; ISSN PRBMDO; ISSN 0163-1829
- Country of Publication:
- United States
- Language:
- English
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