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arXiv · 1502.03593

Controlling structural distortion in the geometrically frustrated layered cobaltate YBaCo4O7+δ by Fe substitution and its role on magnetic correlations

A. K. Bera·S. M. Yusuf·S. S. Meena·Chanchal Sow·P. S. Anil Kumar·S. Banerjee
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Abstract

Effects of Fe-substitution on the crystal structure and magnetic correlations of the geometrically frustrated antiferromagnets YBaCo4-xFexO7+δ (x = 0, 0.2, 0.4, 0.5, 0.6, and 0.8) have been studied by neutron diffraction, Mössbauer spectroscopy, and ac susceptibility. The compounds YBaCo4-xFexO7+δ have a special layered-type crystal structure with an alternating Kagomé (6c site) and triangular (2a site) layers along the c axis. Fe3+ ions are found to be substituted at both the crystallographic 2a and 6c sites of Co ions. Mössbauer results show a high spin state of Fe3+ ions in a tetrahedral coordination. A reduction in the distortion of the Kagomé lattice has been observed with the Fe-substitution. The correlation length of the short-range antiferromagnetic ordering decreases with the Fe-substitution. The sharpness of the magnetic transition also decreases with the Fe-substitution.

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A. K. Bera, S. M. Yusuf, S. S. Meena, Chanchal Sow, P. S. Anil Kumar, S. Banerjee. 2015-02-12. Controlling structural distortion in the geometrically frustrated layered cobaltate YBaCo4O7+δ by Fe substitution and its role on magnetic correlations. https://doi.org/10.1088/2053-1591%2F2%2F2%2F026102

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