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Evidence of a structural anomaly at 14 K in polymerised CsC60

S. Rouziere·S. Margadonna·K. Prassides·A. N. Fitch
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Abstract

We report the results of a high-resolution synchrotron X-ray powder diffraction study of polymerised CsC$_{60}$ in the temperature range 4 to 40 K. Its crystal structure is monoclinic (space group I2/m), isostructural with RbC$_{60}$. Below 14 K, a spontaneous thermal contraction is observed along both the polymer chain axis, $a$ and the interchain separation along [111], $d_1$. This structural anomaly could trigger the occurrence of the spin-singlet ground state, observed by NMR at the same temperature.

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S. Rouziere, S. Margadonna, K. Prassides, A. N. Fitch. 2000-02-27. Evidence of a structural anomaly at 14 K in polymerised CsC60. https://doi.org/10.1209/epl%2Fi2000-00354-1

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