Competing Ordering Modes in the Distorted Quantum Kagome Material Clinoatacamite Cu$_2$Cl(OH)$_3$

L. Stödter; C. Kastner; H. O. Jeschke; M. Reehuis; E. Chan; M. -H. Lemée-Cailleau; K. Beauvois; B. Ouladdiaf; F. Yokaichiya; F. Bert; T. J. Hicken; J. A. Krieger; H. Luetkens; J. L. Allen; R. Feyerherm; M. Tovar; D. Menzel; A. U. B. Wolter; B. Büchner; K. C. Rule; F. J. Litterst; U. K. Rößler; S. Süllow

arXiv · 2601.21024

Competing Ordering Modes in the Distorted Quantum Kagome Material Clinoatacamite Cu$_2$Cl(OH)$_3$

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Abstract

We have studied the magnetic properties of clinoatacamite Cu$_2$Cl(OH)$_3$, the parent compound of the quantum spin liquid candidate herbertsmithite and a longstanding puzzle among frustrated quantum magnets. As we reveal using density-functional theory, clinoatacamite belongs to the class of distorted kagome antiferromagnets with the kagome plane being embedded into a low-symmetry crystal structure. By means of thermodynamic measurements, muon spin rotation/relaxation as well as neutron diffraction on single crystals, we find in zero magnetic field complex behavior below $T_\mathrm{I}$ = 18.1 K which unfolds in three temperature regions I-III. We propose this complexity in multicritical clinoatacamite to arise from the competition of antiferromagnetic ordering modes from the underconstrained manifold of modes, which can lead to a metamagnetic texture in zero field.

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L. Stödter, C. Kastner, H. O. Jeschke, M. Reehuis, E. Chan, M. -H. Lemée-Cailleau, K. Beauvois, B. Ouladdiaf, F. Yokaichiya, F. Bert, T. J. Hicken, J. A. Krieger, H. Luetkens, J. L. Allen, R. Feyerherm, M. Tovar, D. Menzel, A. U. B. Wolter, B. Büchner, K. C. Rule, F. J. Litterst, U. K. Rößler, S. Süllow. 2026-01-28. Competing Ordering Modes in the Distorted Quantum Kagome Material Clinoatacamite Cu$_2$Cl(OH)$_3$. https://arxiv.org/abs/2601.21024

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