Low to High Spin-State Transition Induced by Charge Ordering in Antiferromagnetic <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>YBaCo</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow><mrow><msub><mrow><mi>O</mi></mrow><mrow><mn>5</mn></mrow></msub></mrow></math></span>

T. Vogt; P. M. Woodward; P. Karen; B. A. Hunter; P. Henning; A. R. Moodenbaugh

doi:10.1103/PhysRevLett.84.2969

Low to High Spin-State Transition Induced by Charge Ordering in Antiferromagnetic ${YBaCo}_{2} O_{5}$

T. Vogt, P. M. Woodward, P. Karen, B. A. Hunter, P. Henning, and A. R. Moodenbaugh

Phys. Rev. Lett. 84, 2969 – Published 27 March 2000

Abstract

The oxygen-deficient double perovskite ${YBaCo}_{2} O_{5}$ , containing corner-linked ${CoO}_{5}$ square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital ordering and long-range ${Co}^{2 +} / {Co}^{3 +}$ charge ordering occur as well as a change in the ${Co}^{2 +}$ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and charge ordering.

Received 4 August 1999

DOI:https://doi.org/10.1103/PhysRevLett.84.2969

Authors & Affiliations

T. Vogt¹, P. M. Woodward², P. Karen³, B. A. Hunter⁴, P. Henning¹, and A. R. Moodenbaugh⁵

¹Physics Department, Brookhaven National Laboratory, Upton, New York 11973-5000
²Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210-1185
³Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo, Norway
⁴Australian Nuclear Science & Technology Organization, Private Mail Bag 1, Menai, NSW 2234, Australia
⁵Department of Applied Sciences, Brookhaven National Laboratory, Upton, New York 11973-5000