NMR evidence for Mott-Hubbard localization in „NH3...K3C60
نویسندگان
چکیده
C, H, and K-NMR measurements of (NH3)K3C60 unambiguously demonstrated that its magnetic properties are described as a S51/2 localized spin system over the entire temperature range ~300 K–4.2 K!. A possible antiferromagnetic structure that appeared below 45 K is compatible with the orientational order of KNH3 pairs on the octahedral ~O! site. The present NMR study strongly suggests that the Mott-Hubbard localization occurs due to the removal of the C60 t1u-orbital degeneracy.
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