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arXiv · 1502.03588

Short-range Magnetic Ordering in the Geometrically Frustrated Layered Compound YBaCo4O7 with an Extended Kagomé Structure

A. K. Bera·S. M. Yusuf·S. Banerjee
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Abstract

Structural and magnetic properties of the geometrically frustrated layered compound YBaCo4O7 have been studied by magnetization and neutron diffraction. A layered type crystal structure, with alternating tetrahedral layers of Kagomé and triangular types, along the c axis (hexagonal symmetry, space group P63mc) has been found. The oxygen content of the present compound was determined by iodometric titration to be 7.00{\pm}0.01. Presence of a short-range antiferromagnetic ordering (below TN ~ 110 K) has been concluded from the appearance of an addition broad magnetic peak (at Q ~ 1.35 Å-1) in the neutron diffraction pattern. A staggered chiral type (\sqrt{3}\mult \sqrt{3} ) spin structure in the Kagomé layers has been found. Presence of a significant magneto-structural coupling is concluded from the changes in lattice parameters across the magnetic ordering temperature TN ~ 110 K.

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A. K. Bera, S. M. Yusuf, S. Banerjee. 2015-02-12. Short-range Magnetic Ordering in the Geometrically Frustrated Layered Compound YBaCo4O7 with an Extended Kagomé Structure. https://doi.org/10.1016/j.solidstatesciences.2012.10.028

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