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Internet Electronic Journal of Molecular Design - IEJMD, ISSN 1538-6414, CODEN IEJMAT
| ABSTRACT - Internet Electron. J. Mol. Des. September 2002, Volume 1, Number 9, 443-449 |
Local Aromaticities in Fullerenes as Estimated by the Bond
Resonance Energy Model
Jun-ichi Aihara and Sumio Oe
Internet Electron. J. Mol. Des. 2002, 1, 443-449
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Abstract:
Small fullerenes exhibit large negative nucleus-independent chemical
shift (NICS) values at the centers of many rings even if they are
antiaromatic with negative topological resonance energies (TREs).
This apparent contradiction was examined using the bond resonance
energy (BRE) model. It was found that these diatropic rings consist of
π-bonds with large negative BREs, which suggests that the negative
NICS value does not always represent local aromaticity. π-Electron
currents induced in circuits that surround more than one ring must
contribute significantly to the NICS value at each ring center.
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