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arXiv · 1503.01972

Structural disorder versus chiral magnetism in Cr$_{1/3}$NbS$_2$

V. Dyadkin·F. Mushenok·A. Bosak·D. Menzel·S. Grigoriev·P. Pattison·D. Chernyshov
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Abstract

The crystal structure of a disordered form of Cr$_{1/3}$NbS$_2$ has been characterized using diffraction and inelastic scattering of synchrotron radiation. In contrast to the previously reported symmetry (P6$_3$22), the crystal can be described by a regular twinning of an average P6$_3$ structure with three disordered positions of the Cr ions. Short-range correlations of the occupational disorder result in a quite intense and structured diffuse scattering; a static nature of the disorder was unambiguously attributed by the inelastic x-ray scattering. The diffuse scattering has been modeled using a reverse Monte-Carlo algorithm assuming a disorder of the Cr sub-lattice only. The observed correlated disorder of the Cr sub-lattice reduces the temperature of the magnetic ordering from 130 K to 88 K and drastically modifies the field dependence of the magnetization as it is evidenced by the SQUID magnetometery. We conclude, that in contrast to the helicoidal spin structure assumed for P6$_3$22 form, the compound under study is ferromagnetically ordered with a pronounced in-plane anisotropy.

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V. Dyadkin, F. Mushenok, A. Bosak, D. Menzel, S. Grigoriev, P. Pattison, D. Chernyshov. 2015-03-06. Structural disorder versus chiral magnetism in Cr$_{1/3}$NbS$_2$. https://doi.org/10.1103/physrevb.91.184205

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