A solid-state NMR study of C(70): a model molecule for amorphous carbons.
نویسندگان
چکیده
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.
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عنوان ژورنال:
- Solid state nuclear magnetic resonance
دوره 42 شماره
صفحات -
تاریخ انتشار 2012