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Role of dynamic Jahn-Teller distortions in Na2C60 and Na2CsC60 studied by NMR

V. Brouet·H. Alloul·T. N. Le·S. Garaj·L. Forro
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Abstract

Through 13C NMR spin lattice relaxation (T1) measurements in cubic Na2C60, we detect a gap in its electronic excitations, similar to that observed in tetragonal A4C60. This establishes that Jahn-Teller distortions (JTD) and strong electronic correlations must be considered to understand the behaviour of even electron systems, regardless of the structure. Furthermore, in metallic Na2CsC60, a similar contribution to T1 is also detected for 13C and 133Cs NMR, implying the occurence of excitations typical of JT distorted C60^{2-} (or equivalently C60^{4-}). This supports the idea that dynamic JTD can induce attractive electronic interactions in odd electron systems.

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V. Brouet, H. Alloul, T. N. Le, S. Garaj, L. Forro. 2000-12-12. Role of dynamic Jahn-Teller distortions in Na2C60 and Na2CsC60 studied by NMR. https://doi.org/10.1103/physrevlett.86.4680

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