sup 13 C NMR spectroscopy of K sub x C sub 60 : Phase separation molecular dynamics, and metallic properties

Journal Article · Fri Aug 23 00:00:00 EDT 1991 · Science (Washington, D.C.); (United States)

DOI:https://doi.org/10.1126/science.253.5022.884· OSTI ID:5957103

Tycko, R; Dabbagh, G; Rosseinsky, M J; Murphy, D W; Fleming, R M; Ramirez, A P; Tully, J C ^[1]

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1. AT and T Bell Labs., Murray Hill, NJ (United States)

The results of C nuclear magnetic resonance (NMR) measurements on alkali fullerides K{sub x}C{sub 60} are reported. The NMR spectra demonstrate that material with 0 < x < 3 is in fact a two-phase system at equilibrium, with x = 0 and x = 3. NMR lineshapes indicate that C{sup 3{minus}}{sub 60} ions rotate rapidly in the K{sub 3}C{sub 60} phase at 300 K, while C{sub 60}{sup 6{minus}} ions in the insulating K{sub 6}C{sub 60} phase are static on the time scale of the lineshape measurement. The temperature dependence of the C spin-lattice relaxation rate in the normal state of K{sub 3}C{sub 60} is found to be characteristic of a metal, indicating the important role of the C{sub 60}{sup 3{minus}} ions in the conductivity. From the relaxation measurements, an estimate of the density of electronic states at the Fermi level is derived.

• OSTI ID: 5957103
• Journal Information: Science (Washington, D.C.); (United States), Vol. 253:5022; ISSN 0036-8075
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CARBON COMPOUNDS
ELECTRONIC STRUCTURE
POTASSIUM COMPOUNDS
CARBON 13
EXPERIMENTAL DATA
NMR SPECTRA
SPIN-LATTICE RELAXATION
SUPERCONDUCTIVITY
TEMPERATURE EFFECTS
ALKALI METAL COMPOUNDS
CARBON ISOTOPES
DATA
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
EVEN-ODD NUCLEI
INFORMATION
ISOTOPES
LIGHT NUCLEI
NUCLEI
NUMERICAL DATA
PHYSICAL PROPERTIES
RELAXATION
SPECTRA
STABLE ISOTOPES
360606* - Other Materials- Physical Properties- (1992-)
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