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Oxygen Moment Formation and Canting in Li2CuO2

E. M. L. Chung·G. J. McIntyre·D. McK. Paul·G. Balakrishnan·M. R. Lees
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Abstract

The possibilities of oxygen moment formation and canting in the quasi-1D cuprate Li2CuO2 are investigated using single crystal neutron diffraction at 2 K. The observed magnetic intensities could not be explained without the inclusion of a large ordered oxygen moment of 0.11(1) Bohr magnetons. Least-squares refinement of the magnetic structure of Li2CuO2 in combination with a spin-density Patterson analysis shows that the magnetization densities of the Cu and O atoms are highly aspherical, forming quasi-1D ribbons of localised Cu and O moments. Magnetic structure refinements and low-field magnetization measurements both suggest that the magnetic structure of Li2CuO2 at 2 K may be canted. A possible model for the canted configuration is proposed.

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E. M. L. Chung, G. J. McIntyre, D. McK. Paul, G. Balakrishnan, M. R. Lees. 2003-08-11. Oxygen Moment Formation and Canting in Li2CuO2. https://doi.org/10.1103/physrevb.68.144410

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