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Title: Composition dependence of the structural chemistry and magnetism of Ca{sub 2.5}Sr{sub 0.5}(Ga,Co){sub 1+} {sub x} Mn{sub 2-} {sub x} O{sub 8}

Abstract

Polycrystalline samples of bilayered brownmillerite-like Ca{sub 2.5}Sr{sub 0.5}GaCo{sub 0.15}Mn{sub 1.85}O{sub 8} and Ca{sub 2.5}Sr{sub 0.5}Ga{sub 1.2}Mn{sub 1.8}O{sub 8} have been prepared and characterised by magnetometry and neutron diffraction over a wide temperature range. The structural chemistry and magnetic properties are compared to those of Ca{sub 2.5}Sr{sub 0.5}GaMn{sub 2}O{sub 8}. Ga enrichment has a significant effect on the former but not on the latter, whereas changes in both occur when paramagnetic Co{sup 3+} cations enter the parent phase on the 4-coordinate sites. The coupling between the environment around the 4-coordinate cations and the transition to an antiferromagnetic ordered state that was observed in Ca{sub 2.5}Sr{sub 0.5}GaMn{sub 2}O{sub 8} is not apparent in the cation-substituted compositions, although both show long-range antiferromagnetic order at low temperatures.

Authors:
 [1];  [2];  [3];  [1];  [3]
  1. Department of Chemistry, University of Liverpool, Liverpool L69 7ZD (United Kingdom)
  2. Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QR (United Kingdom). E-mail: peter.battle@chem.ox.ac.uk
  3. Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QR (United Kingdom)
Publication Date:
OSTI Identifier:
20784920
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 179; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2005.11.037; PII: S0022-4596(05)00577-3; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANTIFERROMAGNETISM; CALCIUM COMPOUNDS; CATIONS; COBALT COMPOUNDS; COBALT IONS; COUPLING; GALLIUM COMPOUNDS; MAGNETIC PROPERTIES; MANGANESE COMPOUNDS; NEUTRON DIFFRACTION; OXIDES; PARAMAGNETISM; POLYCRYSTALS; STRONTIUM COMPOUNDS

Citation Formats

Allix, Mathieu, Battle, Peter D., Frampton, Philip P.C., Rosseinsky, Matthew J., and Ruiz-Bustos, Rocio. Composition dependence of the structural chemistry and magnetism of Ca{sub 2.5}Sr{sub 0.5}(Ga,Co){sub 1+} {sub x} Mn{sub 2-} {sub x} O{sub 8}. United States: N. p., 2006. Web. doi:10.1016/j.jssc.2005.11.037.
Allix, Mathieu, Battle, Peter D., Frampton, Philip P.C., Rosseinsky, Matthew J., & Ruiz-Bustos, Rocio. Composition dependence of the structural chemistry and magnetism of Ca{sub 2.5}Sr{sub 0.5}(Ga,Co){sub 1+} {sub x} Mn{sub 2-} {sub x} O{sub 8}. United States. doi:10.1016/j.jssc.2005.11.037.
Allix, Mathieu, Battle, Peter D., Frampton, Philip P.C., Rosseinsky, Matthew J., and Ruiz-Bustos, Rocio. Wed . "Composition dependence of the structural chemistry and magnetism of Ca{sub 2.5}Sr{sub 0.5}(Ga,Co){sub 1+} {sub x} Mn{sub 2-} {sub x} O{sub 8}". United States. doi:10.1016/j.jssc.2005.11.037.
@article{osti_20784920,
title = {Composition dependence of the structural chemistry and magnetism of Ca{sub 2.5}Sr{sub 0.5}(Ga,Co){sub 1+} {sub x} Mn{sub 2-} {sub x} O{sub 8}},
author = {Allix, Mathieu and Battle, Peter D. and Frampton, Philip P.C. and Rosseinsky, Matthew J. and Ruiz-Bustos, Rocio},
abstractNote = {Polycrystalline samples of bilayered brownmillerite-like Ca{sub 2.5}Sr{sub 0.5}GaCo{sub 0.15}Mn{sub 1.85}O{sub 8} and Ca{sub 2.5}Sr{sub 0.5}Ga{sub 1.2}Mn{sub 1.8}O{sub 8} have been prepared and characterised by magnetometry and neutron diffraction over a wide temperature range. The structural chemistry and magnetic properties are compared to those of Ca{sub 2.5}Sr{sub 0.5}GaMn{sub 2}O{sub 8}. Ga enrichment has a significant effect on the former but not on the latter, whereas changes in both occur when paramagnetic Co{sup 3+} cations enter the parent phase on the 4-coordinate sites. The coupling between the environment around the 4-coordinate cations and the transition to an antiferromagnetic ordered state that was observed in Ca{sub 2.5}Sr{sub 0.5}GaMn{sub 2}O{sub 8} is not apparent in the cation-substituted compositions, although both show long-range antiferromagnetic order at low temperatures.},
doi = {10.1016/j.jssc.2005.11.037},
journal = {Journal of Solid State Chemistry},
number = 3,
volume = 179,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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