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Title: Structural phase transition and magnetism in hexagonal SrMnO{sub 3} by magnetization measurements and by electron, x-ray, and neutron diffraction studies

Abstract

The structural and magnetic properties of the hexagonal four-layer form of SrMnO{sub 3} have been investigated by combining magnetization measurements, electron diffraction, and high-resolution synchrotron x-ray and neutron powder diffraction. Below 350 K, there is subtle structural phase transition from hexagonal symmetry (space group P6{sub 3}/mmc) to orthorhombic symmetry (space group C222{sub 1}) where the hexagonal metric is preserved. The second-order phase transition involves a slight tilting of the corner-sharing Mn{sub 2}O{sub 9} units composed of two face-sharing MnO{sub 6} octahedra and the associated displacement of Sr{sup 2+} cations. The phase transition is described in terms of symmetry-adapted displacement modes of the high symmetry phase. Upon further cooling, long range magnetic order with propagation vector k=(0,0,0) sets in below 300 K. The antiferromagnetic structure, analyzed using representation theory, shows a considerably reduced magnetic moment indicating the crucial role played by direct exchange between Mn centers of the Mn{sub 2}O{sub 9} units.

Authors:
; ;  [1];  [2];  [3];  [2];  [4];  [1];  [3]
  1. ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX (United Kingdom)
  2. Laboratoire CRISMAT-UMR, 6508 ENSI CAEN, 6, Marechal Juin, 14050 Caen (France)
  3. (United Kingdom)
  4. European Synchrotron Radiation Facility, BP220, F-38043 Grenoble Cedex (France)
Publication Date:
OSTI Identifier:
20957769
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevB.75.104417; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTIFERROMAGNETIC MATERIALS; ANTIFERROMAGNETISM; ELECTRON DIFFRACTION; EXCHANGE INTERACTIONS; HCP LATTICES; MAGNETIC MOMENTS; MAGNETIC PROPERTIES; MAGNETIZATION; NEUTRON DIFFRACTION; ORTHORHOMBIC LATTICES; PHASE TRANSFORMATIONS; SPACE GROUPS; STRONTIUM COMPOUNDS; STRONTIUM IONS; SYMMETRY; SYNCHROTRONS; X-RAY DIFFRACTION

Citation Formats

Daoud-Aladine, A., Chapon, L. C., Knight, K. S., Martin, C., ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX, Hervieu, M., Brunelli, M., Radaelli, P. G., and Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT. Structural phase transition and magnetism in hexagonal SrMnO{sub 3} by magnetization measurements and by electron, x-ray, and neutron diffraction studies. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.104417.
Daoud-Aladine, A., Chapon, L. C., Knight, K. S., Martin, C., ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX, Hervieu, M., Brunelli, M., Radaelli, P. G., & Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT. Structural phase transition and magnetism in hexagonal SrMnO{sub 3} by magnetization measurements and by electron, x-ray, and neutron diffraction studies. United States. doi:10.1103/PHYSREVB.75.104417.
Daoud-Aladine, A., Chapon, L. C., Knight, K. S., Martin, C., ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX, Hervieu, M., Brunelli, M., Radaelli, P. G., and Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT. Thu . "Structural phase transition and magnetism in hexagonal SrMnO{sub 3} by magnetization measurements and by electron, x-ray, and neutron diffraction studies". United States. doi:10.1103/PHYSREVB.75.104417.
@article{osti_20957769,
title = {Structural phase transition and magnetism in hexagonal SrMnO{sub 3} by magnetization measurements and by electron, x-ray, and neutron diffraction studies},
author = {Daoud-Aladine, A. and Chapon, L. C. and Knight, K. S. and Martin, C. and ISIS facility, Rutherford Appleton Laboratory-CCLRC, Chilton, Didcot, Oxfordshire, OX11 0QX and Hervieu, M. and Brunelli, M. and Radaelli, P. G. and Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT},
abstractNote = {The structural and magnetic properties of the hexagonal four-layer form of SrMnO{sub 3} have been investigated by combining magnetization measurements, electron diffraction, and high-resolution synchrotron x-ray and neutron powder diffraction. Below 350 K, there is subtle structural phase transition from hexagonal symmetry (space group P6{sub 3}/mmc) to orthorhombic symmetry (space group C222{sub 1}) where the hexagonal metric is preserved. The second-order phase transition involves a slight tilting of the corner-sharing Mn{sub 2}O{sub 9} units composed of two face-sharing MnO{sub 6} octahedra and the associated displacement of Sr{sup 2+} cations. The phase transition is described in terms of symmetry-adapted displacement modes of the high symmetry phase. Upon further cooling, long range magnetic order with propagation vector k=(0,0,0) sets in below 300 K. The antiferromagnetic structure, analyzed using representation theory, shows a considerably reduced magnetic moment indicating the crucial role played by direct exchange between Mn centers of the Mn{sub 2}O{sub 9} units.},
doi = {10.1103/PHYSREVB.75.104417},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 10,
volume = 75,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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