Abstract
INTEREST in the alkali-intercalated AxC60 fullerides (where A is an alkali metal and x = 2, 3, 4, 6)1,2 has been greatly enhanced by the discovery of a family of superconducting phases for x = 3 with transition temperatures (Tcs) that are exceeded only by the copper oxide materials3–9. An early structure refinement5 identified K3C60 as a face-centred-cubic (f.c.c.) intercalation phase with two tetra-hedral (T) and one octahedral (O) potassium ion per C60. The other superconducting A3C60 systems are isostructural7. Here we report 87Rb NMR studies of Rb3C60 which show the expected T: O ratio of 2:1 at 440 K. Below 370 K, however, an additional resonance appears; spin-echo double-resonance NMR experiments11,12 show that this arises from a second type of tetrahedral Rb+ site (T′). Thus the bulk of this material has a local symmetry lower than that of the f.c.c. structure derived from X-ray refinements. Models that could account for this include a rotational orientation of C60 that places a C5 ring adjacent to the T′ Rb+ ions. Alternatively, the symmetry lowering might be due to a Jahn-Teller distortion on C3−60, carrier-density modulation or Rb+ clustering. Each of these models could lead to a degree of charge localization and consequent reduction in the density of states and hence in Tc.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Fullerenes, ACS Symp. Ser. 481 (eds Hammond, G. S. & Kuck, V. J.) (Am. chem. Soc., Washington DC, 1992).
Murphy, D. W. et al. J. Phys. Chem. Solids 53, 1321–1332 (1992).
Hebard, A. F. et al. Nature 350, 600–601 (1991).
Holczer, K. et al. Science 252, 1154–1157 (1991).
Stephens, P. W. et al. Nature 351, 632–634 (1991).
Rosseinsky, M. J. et al. Phys. Rev. Lett. 66, 2830–2832 (1991).
Fleming, R. M. et al. Nature 352, 787–788 (1991).
Tanigaki, K. et al. Nature 352, 222–223 (1991).
Kelty, S. P., Chen, C.-C. & Lieber, C. M. Nature 352, 223–224 (1991).
Tycko, R. et al. Phys. Rev. Lett. 67, 1886–1889 (1991).
Kaplan, D. & Hahn, E. L. J. Phys. Radium 19, 821–826 (1958).
Walstedt, R. E. & Wernick, J. H. Phys. Rev. Lett. 20, 856–859 (1968).
Christides, C. et al. Phys. Rev. B46, 12088–12091 (1992).
Zhang, F. C., Ogata, M. & Rice, T. M. Phys. Rev. Lett. 67, 3452–3455 (1991).
Pfeiffer, L., Walstedt, R. E., Bell, R. F. & Kovacs, T. Phys. Rev. Lett. 49, 1162–1165 (1982).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Walstedt, R., Murphy, D. & Rosseinsky, M. Structural distortion in Rb3C60 revealed by 87Rb NMR. Nature 362, 611–613 (1993). https://doi.org/10.1038/362611a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/362611a0
This article is cited by
-
Polymorphism control of superconductivity and magnetism in Cs3C60 close to the Mott transition
Nature (2010)
-
NMR Evidence for C60 Configurational Fluctuations Around Na Sites in Na2CsC60
Journal of Superconductivity and Novel Magnetism (2007)
-
Fullerene local order in Na2CsC60 by23Na NMR
Applied Magnetic Resonance (2004)
-
NMR on alkali fullerides
Applied Magnetic Resonance (1996)
-
87Rb NMR investigations on binary and ternary fullerene compounds: Rb3C60, K2RbC60 and Rb2CsC60
Applied Magnetic Resonance (1996)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.