Covalency Effects in the Magnetic Form Factor of Ir in <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">K</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> Ir<span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi mathvariant="normal">Cl</mi></mrow><mrow><mn>6</mn></mrow></msub></mrow></math></span>

J. W. Lynn; G. Shirane; M. Blume

doi:10.1103/PhysRevLett.37.154

Covalency Effects in the Magnetic Form Factor of Ir in $K_{2}$ Ir ${Cl}_{6}$

J. W. Lynn, G. Shirane, and M. Blume

Phys. Rev. Lett. 37, 154 – Published 19 July 1976

Abstract

We report magnetic-form-factor measurements for Ir in the cubic antiferromagnet $K_{2}$ Ir ${Cl}_{6}$ ( $T_{N} = 3.05$ K). Even though the Ir ions lie on an fcc lattice and are surrounded by octahedra of Cl, the magnetization density deviates strongly from the cubic symmetry that the charge density shows. This unusual asymmetry is dramatically magnified by the large amount of covalent bonding of the single $5 d (t_{2 g})$ magnetic hole to the ${Cl}_{6}$ complex.

Received 10 May 1976

DOI:https://doi.org/10.1103/PhysRevLett.37.154

Authors & Affiliations

J. W. Lynn and G. Shirane^*

Brookhaven National Laboratory, Upton, New York 11973

M. Blume^*,†

Brookhaven National Laboratory, Upton, New York 11973, and State University of New York at Stony Brook, Stony Brook, New York 11794

^*Work performed under the auspices of the U. S. Energy Research and Development Administration.
^†Work performed under the auspices of the National Science Foundation.