Synthesis, structure, and properties of fullerenes

In 1985 the team of Harry Kroto from the University of Sussex and Richard Smalley from Rice University, along with their colleagues, found clear evidence [1] in the mass spectra of laser ablated graphite that clusters of 60 carbon atoms were unusually stable. A second and smaller peak occurred corresponding to 70 carbon atoms. In searching for the explanation of the C60 cluster, the team proposed an elegant soccerball-shaped molecule having icosahedral symmetry. The proposed molecule consisted of threefold-coordinated carbon atoms linked into a spherical structure consisting of 12 pentagons and 20 hexagons. The pentagons serve to curve the otherwise graphitic plane into a closed surface with no dangling bonds. Because of its similarity to geodesic domes, it was named buckminsterfullerene, after the American architect Buckminster Fuller, who studied such structures. Buckyball became the familiar name. The structure of the C70 cluster was proposed to be a slight modification of the buckyball having an extra band of 10 carbon atoms around its waist, giving it a slightly elongated shape. Many other even-numbered carbon clusters were found in mass spectra, and the terminology fullerenes was coined for the group of cage-shaped carbon clusters.