A solid-state NMR study of C(70): a model molecule for amorphous carbons.
We show that natural abundance, solid-state MAS-NMR (13)C INADEQUATE spectra can be recorded for crystallized C(70), using the through-bond J-coupling for the magnetization transfer. The effect of strong J-coupling can be lessened at high magnetic fields, allowing the observation of cross-peaks between close resonances. DFT calculations of the chemical shifts show an excellent agreement with the experimental values. A correlation is observed between the average CCC bond angles and the (13)C chemical shift, offering a way to understand the dispersion of (13)C chemical shifts in nanoporous activated carbons in terms of local deviations from planarity.
CNRS-CEMHTI, UPR 3079, 1D Avenue de la Recherche Scientifique, 45071 Orléans cedex 2, France. michael.deschamps@cnrs-orleans.fr
Michaël
M
Deschamps
Sylvian
S
Cadars
Edouard
E
Gilbert
Philippe
P
Azaïs
Encarnacion
E
Raymundo-Pinero
François
F
Béguin
Dominique
D
Massiot
D002244:Carbon / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008968:Molecular Conformation
D002244:Carbon