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Title: Short-range charge ordering in Ho{sub 0.1}Sr{sub 0.9}CoO{sub 3-x} (0.15{<=}x{<=}0.49)

Abstract

We report the observation of Co{sup 3+}/Co{sup 4+} short-range charge ordering in 10% Ho-doped SrCoO{sub 3-x} by means of high resolution neutron powder diffraction. The associated one-dimensional commensurate modulation, which can be described with the propagation vector q{sub CO}=(0 0 1/2) with respect to the cubic perovskite cell Pm3m, occurs for compositions close to x=0.20, corresponding to a 1:1 Co{sup 3+}/Co{sup 4+} ratio and extends over clusters of finite size (D{approx}250 A). The bond valence sums for the Co{sup 3+} and Co{sup 4+} sites are +3.07(7) and +3.95(11) (x=0.19), very close to their nominal values +3 and +4. We attribute this astonishing observation to the one-dimensional (1D) character of the associated distortion pattern, whose elastic stabilization is eased with respect to the 3D arrays reported for other charge-ordered perovskite oxides.

Authors:
; ;  [1]; ;  [1];  [2];  [3]; ;  [4]
  1. Laboratory for Neutron Scattering, ETH Zuerich and Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)
  2. (Switzerland)
  3. Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)
  4. Laboratory for Solid State Physics, ETH Hoenggerberg, CH-8097 Zurich (Switzerland)
Publication Date:
OSTI Identifier:
20787831
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevB.73.024423; (c) 2006 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; COBALT IONS; COBALT OXIDES; CONCENTRATION RATIO; CUBIC LATTICES; DOPED MATERIALS; HOLMIUM COMPOUNDS; MODULATION; NEUTRON DIFFRACTION; ONE-DIMENSIONAL CALCULATIONS; PEROVSKITE; STRONTIUM COMPOUNDS; VALENCE

Citation Formats

Streule, S., Podlesnyak, A., Mesot, J., Medarde, M., Pomjakushina, E., Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI, Conder, K., Kazakov, S., and Karpinski, J. Short-range charge ordering in Ho{sub 0.1}Sr{sub 0.9}CoO{sub 3-x} (0.15{<=}x{<=}0.49). United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.73.0.
Streule, S., Podlesnyak, A., Mesot, J., Medarde, M., Pomjakushina, E., Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI, Conder, K., Kazakov, S., & Karpinski, J. Short-range charge ordering in Ho{sub 0.1}Sr{sub 0.9}CoO{sub 3-x} (0.15{<=}x{<=}0.49). United States. doi:10.1103/PHYSREVB.73.0.
Streule, S., Podlesnyak, A., Mesot, J., Medarde, M., Pomjakushina, E., Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI, Conder, K., Kazakov, S., and Karpinski, J. Sun . "Short-range charge ordering in Ho{sub 0.1}Sr{sub 0.9}CoO{sub 3-x} (0.15{<=}x{<=}0.49)". United States. doi:10.1103/PHYSREVB.73.0.
@article{osti_20787831,
title = {Short-range charge ordering in Ho{sub 0.1}Sr{sub 0.9}CoO{sub 3-x} (0.15{<=}x{<=}0.49)},
author = {Streule, S. and Podlesnyak, A. and Mesot, J. and Medarde, M. and Pomjakushina, E. and Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI and Conder, K. and Kazakov, S. and Karpinski, J.},
abstractNote = {We report the observation of Co{sup 3+}/Co{sup 4+} short-range charge ordering in 10% Ho-doped SrCoO{sub 3-x} by means of high resolution neutron powder diffraction. The associated one-dimensional commensurate modulation, which can be described with the propagation vector q{sub CO}=(0 0 1/2) with respect to the cubic perovskite cell Pm3m, occurs for compositions close to x=0.20, corresponding to a 1:1 Co{sup 3+}/Co{sup 4+} ratio and extends over clusters of finite size (D{approx}250 A). The bond valence sums for the Co{sup 3+} and Co{sup 4+} sites are +3.07(7) and +3.95(11) (x=0.19), very close to their nominal values +3 and +4. We attribute this astonishing observation to the one-dimensional (1D) character of the associated distortion pattern, whose elastic stabilization is eased with respect to the 3D arrays reported for other charge-ordered perovskite oxides.},
doi = {10.1103/PHYSREVB.73.0},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 2,
volume = 73,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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