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arXiv · 0905.4038

Crystal water induced switching of magnetically active orbitals in CuCl2

M. Schmitt·O. Janson·M. Schmidt·S. Hoffmann·W. Schnelle·S. -L. Drechsler·H. Rosner
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Abstract

The dehydration of CuCl2*2(H2O) to CuCl2 leads to a dramatic change in magnetic behavior and ground state. Combining density functional electronic structure and model calculations with thermodynamical measurements we reveal the microscopic origin of this unexpected incident -- a crystal water driven switching of the magnetically active orbitals. This switching results in a fundamental change of the coupling regime from a three-dimensional antiferromagnet to a quasi one-dimensional behavior. CuCl2 can be well described as a frustrated J1-J2 Heisenberg chain with ferromagnetic exchange J1 and J2/J1 ~ -1.5 for which a helical ground state is predicted.

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M. Schmitt, O. Janson, M. Schmidt, S. Hoffmann, W. Schnelle, S. -L. Drechsler, H. Rosner. 2009-05-25. Crystal water induced switching of magnetically active orbitals in CuCl2. https://doi.org/10.1103/physrevb.79.245119

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