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arXiv · 1010.0230

Understanding complex magnetic order in disordered cobalt hydroxides through analysis of the local structure

James R. Neilson·Brent C. Melot·Daniel P. Shoemaker·Joshua A. Kurzman·Ram Seshadri·Daniel E. Morse
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Abstract

In many ostensibly crystalline materials, unit-cell-based descriptions do not always capture the complete physics of the system due to disruption in long-range order. In the series of cobalt hydroxides studied here, Co(OH)$_{2-x}$(Cl)$_x$(H$_2$O)$_{n}$, magnetic Bragg diffraction reveals a fully compensated Néel state, yet the materials show significant and open magnetization loops. A detailed analysis of the local structure defines the aperiodic arrangement of cobalt coordination polyhedra. Representation of the structure as a combination of distinct polyhedral motifs explains the existence of locally uncompensated moments and provides a quantitative agreement with bulk magnetic measurements and magnetic Bragg diffraction.

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James R. Neilson, Brent C. Melot, Daniel P. Shoemaker, Joshua A. Kurzman, Ram Seshadri, Daniel E. Morse. 2011-01-10. Understanding complex magnetic order in disordered cobalt hydroxides through analysis of the local structure. https://doi.org/10.1103/physrevb.83.094418

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