Planar Hexacoordinate Carbon: A Viable Possibility
10.1126/science.290.5498.1937
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

The viability of molecules with planar hexacoordinate carbon atoms is demonstrated by density-functional theory (DFT) calculations for CB 6 2– , a CB 6 H 2 isomer, and three C 3 B 4 minima. All of these species have six π electrons and are aromatic. Although other C 3 B 4 isomers are lower in energy, the activation barriers for the rearrangements of the three planar carbon C 3 B 4 minima into more stable isomers are appreciable, and experimental observation should be possible. High-level ab initio calculations confirm the DFT results. The planar hexacoordination in these species does not violate the octet rule because six partial bonds to the central carbons are involved.

Bibliography

Exner, K., & Schleyer, P. von R. (2000). Planar Hexacoordinate Carbon: A Viable Possibility. Science, 290(5498), 1937–1940.

Authors 2
  1. Kai Exner (first)
  2. Paul von Ragué Schleyer (additional)
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  41. Supplemental material is available at www.sciencemag.org/cgi/content/full/290/5498/1937/DC1.
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  46. We thank H. Prinzbach Freiburg for his encouragement. This work was supported by the Fonds der Chemischen Industrie through a postdoctoral fellowship (K.E.).
Dates
Type When
Created 23 years, 1 month ago (July 27, 2002, 5:52 a.m.)
Deposited 1 year, 7 months ago (Jan. 13, 2024, 3:49 a.m.)
Indexed 1 day, 1 hour ago (Aug. 28, 2025, 8:25 a.m.)
Issued 24 years, 8 months ago (Dec. 8, 2000)
Published 24 years, 8 months ago (Dec. 8, 2000)
Published Print 24 years, 8 months ago (Dec. 8, 2000)
Funders 0

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@article{Exner_2000, title={Planar Hexacoordinate Carbon: A Viable Possibility}, volume={290}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.290.5498.1937}, DOI={10.1126/science.290.5498.1937}, number={5498}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Exner, Kai and Schleyer, Paul von Ragué}, year={2000}, month=dec, pages={1937–1940} }