Geometrical and Electronic Rules in Fullerene‐Based Compounds

Abstract

The discovery of buckminsterfullerene C(60) opened up a new scientific area and stimulated the development of nanoscience and nanotechnology directly. Fullerene science has since emerged to include fullerenes, endohedral fullerenes (mainly metallofullerenes), exofullerenes, and carbon nanotubes as well. Herein, we look back at the development of fullerene science from the perspective of epistemology by highlighting the proposed main rules or criteria for understanding and predicting the structures and stability of fullerene-based compounds. We also point out that a rule or criterion may contribute significantly to the corresponding discipline and suggest that two unsolved issues in fullerene science are the addition patterns of fullerene derivatives and the structures and stability of nonclassical fullerenes.

General rules for predicting the local aromaticity of carbon polyhedra

“…It is important to note that our predicted relative aromaticity order based on the BRE method is in very good agreement with the results of Gan et al [36,37] for the 4/5 and 4/4 type bonds. However, we do not accept the position in the relative aromaticity order predicted by Gan et al for the 6/6 bond nor for those bonds which contain heptagons.…”

“…Gan et al [36,37] performed calculations on carbon polyhedra that consisted of squares, pentagons, hexagons, and heptagons using the density functional theory (DFT) method, and based on their binding energy, the following stability order of subunits within carbon polyhedrons was determined: 6/7 > 4/6 > 5/5 > 4/5 > 4/4 4/7 > 5/7 > 7/7 > 5/6 > 6/6…”

Carbon arc production of heptagon-containing fullerene[68]

“…At a temperature above 2,100 K, however, the heptagon-incorporating C 68 becomes the most abundant species as entropic factors have a decisive role in their relative Gibbs free energies and relative concentrations/abundances (Supplementary Tables S8 and S9). In agreement with this prediction about the temperature-dependent stability, several theoretical studies have suggested the prevalence of heptagons in the world of the cage-closed all-carbon allotropes1112131415161718192021232425263536. Experimental corroboration of such a prevalence of heptagons heavily depends on the in situ capture of heptafullerene in the carbon clustering venue for the growth of the whole family of fullerenes.…”

“…A bare heptafullerene[62] with C s -symmetry23, as well as the exohedral heptagon-containing C 68 X 4 (X=H, F, Cl)24, has been calculated to be more stable than all the classical non-heptagon isomers. Very recently, a number of smaller heptafullerenes (C 46 –C 58 ) have also been suggested to be viable182526. However, experimental confirmation of the existence of heptagons in the family of fullerenes is still a challenge for chemists and physicists.…”

A computational study on Sc2S@C68 and Sc2O2@C68

“…2 Since the invention of the resistive heating method, 3 a series of monometallofullerenes and dimetallofullerenes were synthesized in bulk quantities. 2 Since the invention of the resistive heating method, 3 a series of monometallofullerenes and dimetallofullerenes were synthesized in bulk quantities.…”