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arXiv · 0808.1969

Determination of the single-ion anisotropy energy in a S = 5/2 kagome antiferromagnet using X-ray absorption spectroscopy

M. A. de Vries·T. K. Johal·A. Mirone·J. S. Claydon·G. J. Nilsen·H. M. Ronnow·G. van der Laan·A. Harrison
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Abstract

We report x-ray absorption and x-ray linear dichroism measurements at the Fe L2,3 edges of the geometrically frustrated systems of potassium and hydronium iron jarosite. Comparison with simulated spectra, involving ligand-field multiplet calculations modelling the 3d-2p hybridization between the iron ion and the oxygen ligands, has yielded accurate estimates for the ligand metal-ion hybridization and the resulting single-ion crystal field anisotropy energy. Using this method we provide an experimentally verified scenario for the appearance of a single-ion anisotropy in this nominally high-spin 3d5 orbital singlet 6S system, which accounts for features of the spin-wave dispersion in the long-range ordered ground state of potassium iron jarosite.

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M. A. de Vries, T. K. Johal, A. Mirone, J. S. Claydon, G. J. Nilsen, H. M. Ronnow, G. van der Laan, A. Harrison. 2008-12-15. Determination of the single-ion anisotropy energy in a S = 5/2 kagome antiferromagnet using X-ray absorption spectroscopy. https://doi.org/10.1103/physrevb.79.045102

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