Nanomaterials - Buckyball
20.10The structure of C60 is a truncated (T = 3) icosahedron, which resembles a football of the kind made of twenty hexagons and twelve Pentagon, with a carbon atom at the nodes in each polygon and a bond along each edge of polygon.
Van der Waals diameter of a C60 molecule is about 1 nanometer (nm). The core of the core diameter of a C60 molecule is about 0.7 nm.
The C60 molecule has two bond lengths. The 6:6 ring bonds (between two hexagons) can be considered "double bonds" and are shorter than the 6:5 bonds (between a hexagon and a pentagon). Its average bond length is 1.4 angstroms.
Boron buckyball
A new type of bucky ball uses boron atoms instead of the usual carbon has been predicted and described by researchers at Rice University. B-80 structure is expected to be more stable than the C 60 bucky ball. One reason for this, which the researchers is that the B-80 is actually more like the original geodesic dome structure popularized by Buckminster Fuller, using triangles rather than hexagons. But this work has been the subject of much criticism by quantum chemists As it was concluded that the expected Ih vibrationally symmetric structure was unstable and the resulting cage undergoes a spontaneous symmetry breaking gives a puck cage with rare Th symmetry (symmetry in volleyball) The number of six rings of carbon in this molecule is 20 and the number of five member rings is 12.Variations of buckyballs
Another fairly common buckminsterfullerene is C70,but fullerenes with 72, 76, 84 and even up to 100 carbon atoms are commonly obtained.
In mathematical terms, the structure of a fullerene is a trivalent convex polyhedron with pentagonal and hexagonal faces. In graph theory, the term fullerene refers to any 3-regular, planar graph with all faces of size 5 or 6 (including the external face). It follows from Euler's polyhedron formula, |V|-|E|+|F| = 2, (where |V|, |E|, |F| indicate the number of vertices, edges, and faces), that there are exactly 12 pentagons in a fullerene and |V|/2-10 hexagons.
Nanomaterials - Variations
20.06Since the discovery of fullerenes in 1985, structural variations on fullerenes have evolved well beyond the individual clusters themselves. Examples include:
- buckyball clusters: smallest member is C 20 (unsaturated version of dodecahedrane) and the most common is C 60;
- nanotubes: hollow tubes of very small dimensions, having single or multiple walls; potential applications in electronics industry;
- megatubes: larger in diameter than nanotubes and prepared with walls of different thickness; potentially used for the transport of a variety of molecules of different sizes;
- polymers: chain, two-dimensional and three-dimensional polymers are formed under high pressure high temperature conditions
- nano"onions": spherical particles based on multiple carbon layers surrounding a buckyball core; proposed for lubricants;
- linked "ball-and-chain" dimers: two buckyballs linked by a carbon chain;
- fullerene rings
Nanomaterials - Fullerene
19.57Full Clean is a family of carbon allotropes, molecules composed entirely of carbon in the form of a hollow sphere, ellipsoid, tube or plane. Spherical fuller's also known as bucky balls, and cylindrical them called carbon nanotubes or buckytubes. Grapher is an example of a planar format full clean sheets. Fuller's is similar in structure to graphite, which consists of stacked sheets of linked hexagonal rings, but may also contain pentagonal (or sometimes heptagonal) rings that would prevent a sheet from the planar format.
The full clean was discovered in 1985 by Robert Curl, Harold Kroto and Richard Smalley at the University of Sussex and Rice University who named it after Richard Buckminster Fuller, whose geodesic domes similar.
Prediction and discovery
Minute quantities of fuller's, in the form of C60, C70, C76 and C84 molecules that are produced in nature, hidden in soot and formed by lightning discharges in the atmosphere. Recently Buckminsterfullerenes was found in a family of minerals known as Shungites in Karelia, Russia. [citation needed]
The existence of C60 was predicted by Eiji Osawa of Toyohashi University of Technology in a Japanese magazine in 1970. He noticed that the structure of a molecule corannulene was a subset of a soccer-ball shape, and he put forward the hypothesis that a full ball shape could also exist. His idea was reported in Japanese magazines, but did not reach Europe or the USA.
Naming
Buckminsterfullerene (C60) was named after Richard Buckminster Fuller, a noted architectural modeler who popularized the geodesic dome. Since buckminsterfullerenes have a similar shape to that sort of dome, the name was thought to be appropriate. As the discovery of the fullerene family came after buckminsterfullerene, the shortened name 'fullerene' was used to refer to the family of fullerenes.