who discovered fullerene (an allotrope of carbon)
Carbon group


, germanium's is 123 picometers, tin's is 141 picometers, and lead's is 175 picometers. Carbon has multiple allotropes. The most common is graphite, which is carbon in the form of stacked sheets. Another form of carbon is diamond, but this is relatively rare. Amorphous carbon is a third allotrope of carbon; it is a component of soot. Another allotrope of carbon is a fullerene, which has the form of sheets of carbon atoms folded into a sphere. A fifth allotrope of carbon, discovered in
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Allotropes of carbon


width of a human hair), while they can be up to several centimeters in length. There are two main types of nanotubes: single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs). Carbon nanobuds are a newly discovered allotrope of carbon in which fullerene like "buds" are covalently attached to the outer sidewalls of the carbon nanotubes. This hybrid material has useful properties of both fullerenes and carbon nanotubes. For instance, they have been found to be exceptionally good field emitters. Schwarzites are negatively
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Carbon nanobud


In nanotechnology, a carbon nanobud is a material that combines carbon nanotubes and spheroidal fullerenes, both allotropes of carbon, in the same structure, forming "buds" attached to the tubes. Carbon nanobuds were discovered and synthesized in 2006. In this material, fullerenes are covalently bonded to the outer sidewalls of the underlying nanotube. Consequently, nanobuds exhibit properties of both carbon nanotubes and fullerenes. For instance, the mechanical properties and the electrical conductivity of the nanobuds are similar to those of corresponding carbon nanotubes. However, because of
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Compounds of carbon


the allotropes of carbon (diamond, graphite, and the fullerenes) blossomed with the discovery of buckminsterfullerene in 1985, as additional fullerenes and their various derivatives were discovered. One such class of derivatives is inclusion compounds, in which an ion is enclosed by the all-carbon shell of the fullerene. This inclusion is denoted by the "@" symbol in endohedral fullerenes. For example, an ion consisting of a lithium ion trapped within buckminsterfullerene would be denoted Li@C. As with any other ionic compound, this complex ion could in
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Carbon


The three relatively well-known allotropes of carbon are amorphous carbon, graphite, and diamond. Once considered exotic, fullerenes are nowadays commonly synthesized and used in research; they include buckyballs, carbon nanotubes, carbon nanobuds and nanofibers. Several other exotic allotropes have also been discovered, such as lonsdaleite, glassy carbon, carbon nanofoam and linear acetylenic carbon (carbyne). Graphene is a two-dimensional sheet of carbon with the atoms arranged in a hexagonal lattice. As of 2009, graphene appears to be the strongest material ever
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Carbon


carbone" (Latin "carbonum") for the element in graphite which was given off as a gas upon burning graphite. Antoine Lavoisier then listed carbon as an element in his 1789 textbook. A new allotrope of carbon, fullerene, that was discovered in 1985 includes nanostructured forms such as buckyballs and nanotubes. Their discoverers – Robert Curl, Harold Kroto and Richard Smalley – received the Nobel Prize in Chemistry in 1996. The resulting renewed interest in new forms lead to the discovery of further exotic allotropes, including glassy carbon,
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Carbon nanotube


building blocks. These scaffolds possess macro-, micro-, and nano-structured pores, and the porosity can be tailored for specific applications. These 3D all-carbon scaffolds/architectures may be used for the fabrication of the next generation of energy storage, supercapacitors, field emission transistors, high-performance catalysis, photovoltaics, and biomedical devices, implants, and sensors. Carbon nanobuds are a newly created material combining two previously discovered allotropes of carbon: carbon nanotubes and fullerenes. In this new material, fullerene-like "buds
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Allotropes of carbon


true amorphous carbon under normal conditions. The "buckminsterfullerenes", or usually just "fullerenes" or "buckyballs" for short, were discovered in 1985 by a team of scientists from Rice University and the University of Sussex, three of whom were awarded the 1996 Nobel Prize in Chemistry. They are named for the resemblance to the geodesic structures devised by Richard Buckminster "Bucky" Fuller. Fullerenes are positively curved molecules of varying sizes composed entirely of carbon, which take the form of a hollow sphere, ellipsoid, or tube
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Nanomaterials


the term nanoparticle for all shapes. Nanoparticles have all three dimensions on the nanoscale. Nanoparticles can also be embedded in a bulk solid to form a nanocomposite. The fullerenes are a class of allotropes of carbon which conceptually are graphene sheets rolled into tubes or spheres. These include the carbon nanotubes (or silicon nanotubes) which are of interest both because of their mechanical strength and also because of their electrical properties. The first fullerene molecule to be discovered, and the family's namesake, buckminsterfullerene (C), was prepared in
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Buckminster Fuller


, Kenneth Snelson, Robert Anton Wilson and Stewart Brand. An allotrope of carbon, fullerene—and a particular molecule of that allotrope C (buckminsterfullerene or buckyball) has been named after him. The Buckminsterfullerene molecule, which consists of 60 carbon atoms, very closely resembles a spherical version of Fuller's geodesic dome. The 1996 Nobel prize in chemistry was given to Kroto, Curl, and Smalley for their discovery of the fullerene. He is quoted in the lyric of "The Tower of Babble" in the musical "Godspell
3594988
Harry Kroto


significant for the discovery of a new allotrope of carbon known as a fullerene. Other allotropes of carbon include graphite, diamond and graphene. Harry Kroto's 1985 paper entitled "C60: Buckminsterfullerine", published with colleagues J. R. Heath, S. C. O'Brien, R. F. Curl, and R. E. Smalley, was honored by a Citation for Chemical Breakthrough Award from the Division of History of Chemistry of the American Chemical Society, presented to Rice University in 2015. The discovery of fullerenes was recognized in 2010 by the designation of a
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Fullerene


also called carbon nanotubes or buckytubes. The bulk solid form of pure or mixed fullerenes is called fullerite. Fullerenes had been predicted for some time, but only after their accidental synthesis in 1985 were they detected in nature and outer space. The discovery of fullerenes greatly expanded the number of known allotropes of carbon, which had previously been limited to graphite, diamond, and amorphous carbon such as soot and charcoal. They have been the subject of intense research, both for their chemistry and for their technological applications, especially in materials
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History of nanotechnology


as R Corona Borealis. The result of this collaboration was the discovery of C and the fullerenes as the third allotropic form of carbon. Subsequent discoveries included the endohedral fullerenes, and the larger family of fullerenes the following year. The discovery of carbon nanotubes is largely attributed to Sumio Iijima of NEC in 1991, although carbon nanotubes have been produced and observed under a variety of conditions prior to 1991. Iijima's discovery of multi-walled carbon nanotubes in the insoluble material of arc-burned graphite rods in 1991 and Mintmire,
12604651
Truncated icosahedron


model of the Buckminsterfullerene (fullerene) (C), or "buckyball," molecule, an allotrope of elemental carbon, discovered in 1985. The diameter of the football and the fullerene molecule are 22 cm and about 0.71 nm, respectively, hence the size ratio is ≈31,000,000:1. In popular craft culture, large sparkleballs can be made using a icosahedron pattern and plastic, styrofoam or paper cups. A truncated icosahedron with "solid edges" by Leonardo da Vinci appears as an illustration in Luca Pacioli's book De divina proportione
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Carbocatalysis


of ethylbenzene to styrene discovered in the 1970s. Also in the industrial process of (non-oxidative) dehydrogenation of ethylbenzene, the potassium-promoted iron oxide catalyst is coated with a carbon layer as the active phase. In another early example, a variety of substituted nitrobenzenes were reduced to the corresponding aniline using hydrazine and graphite as the catalyst. The discovery of nanostructured carbon allotropes such as carbon nanotubes, fullerenes, or graphene promoted further developments. Oxidized carbon nanotubes were used to dehydrogenate n-butane to 1-butene, and to
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Solubility of fullerenes


The solubility of fullerenes is generally low. Carbon disulfide dissolves 8g/L of C60, and the best solvent (1-chloronaphthalene) dissolves 53 g/L. up Still, fullerenes are the only known allotrope of carbon that can be dissolved in common solvents at room temperature. Besides those two, good solvents for fullerenes include 1,2-dichlorobenzene, toluene, p-xylene, and 1,2,3-tribromopropane. Fullerenes are highly insoluble in water,and practically insoluble in methanol. Solutions of pure C (buckminsterfullerene) have a deep purple color. Solutions of C
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Organic compound


open valence is on a carbon atom. For historical reasons discussed below, a few types of carbon-containing compounds, such as carbides, carbonates, simple oxides of carbon (for example, CO and CO), and cyanides are considered inorganic. Allotropes of carbon, such as diamond, graphite, fullerenes, and carbon nanotubes are also excluded because they are simple substances composed of only a single element and therefore allotropes are not generally considered to be chemical "compounds". For many centuries, Western physicians and chemists believed
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Linear acetylenic carbon


acceptance of carbyne as a true carbon allotrope. The mysterious carbyne still attracted scientists with its possible extraordinary properties. In 1984, a group at Exxon reported the detection of clusters with even numbers of carbons, between 30 and 180, in carbon evaporation experiments, and attributed them to polyyne carbon. However, these clusters later were identified as fullerenes. In 1991, carbyne was allegedly detected among various other allotropes of carbon in samples of amorphous carbon black vaporized and quenched by shock waves produced by shaped explosive charges. In 1995,
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Fullerene


A fullerene is an allotrope of carbon whose molecule consists of carbon atoms connected by single and double bonds so as to form a closed or partially closed mesh, with fused rings of five to seven atoms. The molecule may be a hollow sphere, ellipsoid, tube, or many other shapes and sizes. Graphene (isolated atomic layers of graphite), which is a flat mesh of regular hexagonal rings, can be seen as an extreme member of the family. Fullerenes with a closed mesh topology are informally denoted by their empirical
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Carbon monofluoride


gaseous fluorocarbons such as tetrafluorocarbon, CF, and tetrafluoroethylene, CF. In a similar fashion the recently found carbon allotrope fullerene, C reacts with fluorine gas to give fullerene fluorides with stoichiometries up to CF. A precursor of carbon monofluoride is the fluorine-graphite intercalation compound, also called fluorine-GIC. Other intercalation fluorides of carbon are Graphite fluoride is a procursor for preparation of graphene fluoride by a liquid phase exfoliation. Carbon monofluoride is used as a high-energy-density cathode material in lithium batteries of the "BR
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Fullerene


C in carbon disulfide. Still, fullerenes are the only known allotrope of carbon that can be dissolved in common solvents at room temperature. Among the best solvents is 1-chloronaphthalene, which will dissolve 51 g/L of C. Solutions of pure buckminsterfullerene have a deep purple color. Solutions of are a reddish brown. The higher fullerenes to have a variety of colors. Millimeter-sized crystals of and , both pure and solvated, can be grown from benzene solution. Crystallization of C60 from benzene solution below 30 °C (when
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Contorted aromatics


Contorted aromatics or more precisely contorted polycyclic aromatic hydrocarbons represent a unique class of polycyclic aromatic hydrocarbons (PAHs) in which the fused aromatic molecules deviate from the usual planarity. The comparison of structures of graphene and fullerene can help comprehend the origin of curved pi surfaces and contortion in PAHs. Both graphene and fullerene bear resemblance in having sp hybridized carbons however, exhibit different geometries (allotropes of carbon). The fact that fullerenes have five membered rings incorporated among six membered rings, makes them spherical whereas graphene remains planar due to the
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Allotropes of carbon


. As of the early twenty-first century, the chemical and physical properties of fullerenes are still under heavy study, in both pure and applied research labs. In April 2003, fullerenes were under study for potential medicinal use — binding specific antibiotics to the structure to target resistant bacteria and even target certain cancer cells such as melanoma. Carbon nanotubes, also called buckytubes, are cylindrical carbon molecules with novel properties that make them potentially useful in a wide variety of applications (e.g., nano-electronics, optics, materials applications
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Graphene


Graphene (/ˈɡræfiːn/) is an allotrope of carbon in the form of a two-dimensional, atomic-scale, hexagonal lattice in which one atom forms each vertex. It is the basic structural element of other allotropes, including graphite, charcoal, carbon nanotubes and fullerenes. It can also be considered as an indefinitely large aromatic molecule, the ultimate case of the family of flat polycyclic aromatic hydrocarbons. Graphene has a unique set of properties which set it apart from other materials. In proportion to its thickness, it is about
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60 (number)


, 4, 5, a type of Pythagorean triple. The first fullerene to be discovered was buckminsterfullerene C, an allotrope of carbon with 60 atoms in each molecule, arranged in a truncated icosahedron. This ball is known as a buckyball, and looks like a soccer ball. The atomic number of neodymium is 60, and cobalt-60 (Co) is a radioactive isotope of cobalt. The electrical utility frequency in western Japan, South Korea, Taiwan, the Philippines, Saudi Arabia, the United States, and several other countries
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Macromolecular cages


. The polymers that are typically used to make the polymer based macromolecular cages are made with star shaped polymers or nonlinear polymer precursors. The molecular size of the polymeric macromolecular cage is controlled by the molecular weight of the star-shaped polymer or branched polymer. The macromolecular cages made from non-linear polymers are designed to have molecular recognition, respond to external stimuli and self-assemble into higher order structures. Fullerenes are a class of carbon allotropes that were first discovered in 1985 and are also an example of macromolecular cages.
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Carbon nanotube


Carbon nanotubes (CNT) are a class of nanomaterials that consist of a two-dimensional hexagonal lattice of carbon atoms, bent and joined in one direction so as to form a hollow cylinder. Carbon nanotubes are one of the allotropes of carbon, specifically a class of fullerenes, intermediate between the buckyballs (closed shells) and graphene (flat sheets). Besides these single-wall carbon nanotubes (SWCNTs), the name is also used for multi-wall (MWCNT) variants consisting of two or more nested nanotubes,
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Carbon nanofiber


Carbon nanofibers (CNFs), vapor grown carbon fibers (VGCFs), or vapor grown carbon nanofibers (VGCNFs) are cylindrical nanostructures with graphene layers arranged as stacked cones, cups or plates. Carbon nanofibers with graphene layers wrapped into perfect cylinders are called carbon nanotubes. Carbon has a high level of chemical bonding flexibility, which lends itself to the formation of a number of stable Organic and Inorganic Molecules. Elemental carbon has a number of allotropes(variants) including diamond, graphite, and fullerenes. Though they all consist of elemental carbon
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Allotropes of carbon


Carbon is capable of forming many allotropes (structurally different forms of the same element) due to its valency. Well-known forms of carbon include diamond and graphite. In recent decades many more allotropes, or forms of carbon, have been discovered and researched including ball shapes such as buckminsterfullerene and sheets such as graphene. Larger scale structures of carbon include nanotubes, nanobuds and nanoribbons. Other unusual forms of carbon exist at very high temperatures or extreme pressures. Around 500 hypothetical 3-periodic allotropes of carbon are known at the present time
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Rodney S. Ruoff


understanding of properties of novel materials including nanostructures and 2D materials, especially novel carbon materials (graphene, diamond, nanotubes, sp-sp hybrids, negative curvature carbon, carbon nanofoams, boron nitride allotropes, fullerenes, etc.). Some examples of pioneering studies, among others, include:(i) of the mechanics of C, and of nanotubes, including pullout of inner shell with respect to outer shell of the nanotube, and of a connection between mechanical deformation and structure on the one hand, and chemical reactivity on the other;(ii
144663
ApNano


Havakuk serves as Vice President of Global Sales and Marketing. NIS is specializing in commercial manufacturing of nanoparticles of Inorganic Fullerene-like Tungsten Disulfide(IF-WS₂). The particles are called Inorganic Fullerene-like (IF), because of the and a hollow core – similar to carbon fullerenes. The name “fullerenes” or “buckyballs” came from the architectural modeler Richard Buckminster Fuller, who popularized the geodesic dome. Professor Reshef Tenne discovered Inorganic Fullerene-like nanoparticles (IF-MXy where M- is transition metal and X -
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Richard Smalley


inorganic and semiconductor clusters using pulsed molecular beams and time-of-flight mass spectrometry. As a consequence of this expertise, Robert Curl introduced him to Harry Kroto in order to investigate a question about the constituents of astronomical dust. These are carbon-rich grains expelled by old stars such as R Coronae Borealis. The result of this collaboration was the discovery of C (Known as Buckyballs) and the fullerenes as the third allotropic form of carbon. The research that earned Kroto, Smalley and Curl the Nobel Prize mostly comprised
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Buckypaper


the 60 carbon fullerene (an allotrope of carbon with similar bonding that is sometimes referred to as a "Buckyball" in honor of R. Buckminster Fuller). The generally accepted methods of making CNT films involves the use of non-ionic surfactants, such as Triton X-100 and sodium lauryl sulfate, which improves their dispersibility in aqueous solution. These suspensions can then be membrane filtered under positive or negative pressure to yield uniform films. The van der Waals force's interaction between the nanotube surface and the surfactant can often be mechanically strong
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Fullerene


sensors for their enantiomers. Two theories have been proposed to describe the molecular mechanisms that make fullerenes. The older, “bottom-up” theory proposes that they are built atom-by-atom. The alternative “top-down” approach claims that fullerenes form when much larger structures break into constituent parts. In 2013 researchers discovered that asymmetrical fullerenes formed from larger structures settle into stable fullerenes. The synthesized substance was a particular metallofullerene consisting of 84 carbon atoms with two additional carbon atoms and two yttrium atoms inside the cage
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Fullerene


, nitrogen (azafullerene), oxygen, and phosphorus derivatives. Trimetasphere carbon nanomaterials were discovered by researchers at Virginia Tech and licensed exclusively to Luna Innovations. This class of novel molecules comprises 80 carbon atoms () forming a sphere which encloses a complex of three metal atoms and one nitrogen atom. These fullerenes encapsulate metals which puts them in the subset referred to as metallofullerenes. Trimetaspheres have the potential for use in diagnostics (as safe imaging agents), therapeutics and in organic solar cells. Carbon nanotubes are cylindrical fullerenes. These
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Azafullerene


the broader fullerene research community. Many properties and structures are yet to be discovered for the highly-nitrogen substituted subset of molecules. The first fullerene molecule to be discovered, and the family's namesake, buckminsterfullerene (C), was prepared in 1985 by Richard Smalley, Robert Curl, James Heath, Sean O'Brien, and Harold Kroto at Rice University. A fullerene is any molecule composed entirely of carbon, in the form of a hollow sphere, ellipsoid, tube, and many other shapes. Spherical fullerenes are also called
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Fullerene


atoms instead of the normal four. The shortened named "fullerene" eventually came to be applied to the whole family. Kroto, Curl, and Smalley were awarded the 1996 Nobel Prize in Chemistry for their roles in the discovery of this class of molecules. Kroto and the Rice team already discovered other fullerenes besides C60, and the list was much expanded in the following years. Carbon nanotubes were first discovered and synthesized in 1991. After their discovery, minute quantities of fullerenes were found to be produced in sooty flames, and
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Allotropes of carbon


through carbon under very low pressures. It is extremely unstable, but it is an intermittent product used in the creation of carbenes. Diatomic carbon can also be found under certain conditions. It is often detected via spectroscopy in extraterrestrial bodies, including comets and certain stars. Carbon nanofoam is the fifth known allotrope of carbon, discovered in 1997 by Andrei V. Rode and co-workers at the Australian National University in Canberra. It consists of a low-density cluster-assembly of carbon atoms strung together in a loose three-
8634480
Fullerene


instance, there are 1812 non-isomorphic fullerenes . Note that only one form of , buckminsterfullerene, has no pair of adjacent pentagons (the smallest such fullerene). To further illustrate the growth, there are 214,127,713 non-isomorphic fullerenes , 15,655,672 of which have no adjacent pentagons. Optimized structures of many fullerene isomers are published and listed on the web. Heterofullerenes have heteroatoms substituting carbons in cage or tube-shaped structures. They were discovered in 1993 and greatly expand the overall fullerene class of compounds. Notable examples include boron
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Chaoite


Chaoite, or white carbon, is a mineral described as an allotrope of carbon whose existence is disputed. It was discovered in shock-fused graphite gneiss from the Ries crater in Bavaria. It has been described as slightly harder than graphite, with a reflection colour of grey to white. From its electron diffraction pattern, the mineral has been considered to have a carbyne structure, the linear acetylenic carbon allotrope of carbon. A later report has called this identification, and the very existence of carbyne phases, into question, arguing
4479271
History of chemistry


chemistry calculations. In 1971, Yves Chauvin offered an explanation of the reaction mechanism of olefin metathesis reactions. In 1975, Karl Barry Sharpless and his group discovered stereoselective oxidation reactions including Sharpless epoxidation, Sharpless asymmetric dihydroxylation, and Sharpless oxyamination. In 1985, Harold Kroto, Robert Curl and Richard Smalley discovered fullerenes, a class of large carbon molecules superficially resembling the geodesic dome designed by architect R. Buckminster Fuller. In 1991, Sumio Iijima used electron microscopy to discover a type of cylindrical fullerene known as a carbon nanotube, though earlier
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Allotropy


sheets of graphite), and fullerenes (the carbon atoms are bonded together in spherical, tubular, or ellipsoidal formations). The term "allotropy" is used for elements only, not for compounds. The more general term, used for any crystalline material, is polymorphism. Allotropy refers only to different forms of an element within the same phase (i.e.: solid, liquid or gas states); differences in these states alone would not constitute examples of allotropy. For some elements, allotropes have different molecular formulae despite difference
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Phase (matter)


other forms. Polymorphism is the ability of a solid to exist in more than one crystal form. For pure chemical elements, polymorphism is known as allotropy. For example, diamond, graphite, and fullerenes are different allotropes of carbon. When a substance undergoes a phase transition (changes from one state of matter to another) it usually either takes up or releases energy. For example, when water evaporates, the increase in kinetic energy as the evaporating molecules escape the attractive forces of the liquid is reflected in a decrease in
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Allotropes of carbon


, etc.). They exhibit extraordinary strength, unique electrical properties, and are efficient conductors of heat. Inorganic nanotubes have also been synthesized. A nanotube is a member of the fullerene structural family, which also includes buckyballs. Whereas buckyballs are spherical in shape, a nanotube is cylindrical, with at least one end typically capped with a hemisphere of the buckyball structure. Their name is derived from their size, since the diameter of a nanotube is on the order of a few nanometers (approximately 50,000 times smaller than the
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James R. Heath


a fullerene. Other allotropes of carbon include graphite, diamond and graphene. James R. Heath's 1985 paper entitled "C60: Buckminsterfullerine", published with colleagues Harry Kroto, S. C. O’Brien, R. F. Curl, and R. E. Smalley, was honored by a Citation for Chemical Breakthrough Award from the Division of History of Chemistry of the American Chemical Society, presented to Rice University in 2015. Heath is known for publishing an architecture demonstration of molecular computers, or moletronics. In moletronics, single molecules serve as switches, "
5371277
Richard Smalley


(1986). Although only three people can be cited for a Nobel Prize, graduate students James R. Heath, Yuan Liu, and Sean C. O'Brien participated in the work. Smalley mentioned Heath and O'Brien in his Nobel Lecture. Heath went on to become a professor at California Institute of Technology (Caltech) and O'Brien joined Texas Instruments and is now at MEMtronics. Yuan Liu is a Senior Staff Scientist at Oak Ridge National Laboratory. This research is significant for the discovery of a new allotrope of carbon known as a fullerene
6273630
Richard Smalley


. Other allotropes of carbon include graphite, diamond and graphene. Harry Kroto's 1985 paper entitled "C60: Buckminsterfullerine", published with colleagues J. R. Heath, S. C. O'Brien, R. F. Curl, and R. E. Smalley, was honored by a Citation for Chemical Breakthrough Award from the Division of History of Chemistry of the American Chemical Society, presented to Rice University in 2015. The discovery of fullerenes was recognized in 2010 by the designation of a National Historic Chemical Landmark by the American Chemical Society at the Richard E. Smalley
6273631
20th century in science


In 1985, Harold Kroto, Robert Curl and Richard Smalley discovered fullerenes, a class of large carbon molecules superficially resembling the geodesic dome designed by architect R. Buckminster Fuller. In 1991, Sumio Iijima used electron microscopy to discover a type of cylindrical fullerene known as a carbon nanotube, though earlier work had been done in the field as early as 1951. This material is an important component in the field of nanotechnology. In 1994, Robert A. Holton and his group achieved the first total synthesis of Taxol. In 1995, Eric
22004423
Carbon nanobud


of inactive catalyst particles. There are multiple methods that were used in order to discover the fullerenes on the single wall carbon nanotube surfaces, each giving its own contribution to what is currently known about nanobuds. A few of these methods are ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM), and scanning tunneling microscopy (STM). To look even further into the functionality of CNBs and how the single wall carbon nanotubes interact with the fullerenes to produce the nanobuds, calculations were done. The
5352621
Fullerene


Results of such calculations can be compared with experimental results. Fullerene is an unusual reactant in many organic reactions such as the Bingel reaction discovered in 1993. Researchers have been able to increase the reactivity of fullerenes by attaching active groups to their surfaces. Buckminsterfullerene does not exhibit "superaromaticity": that is, the electrons in the hexagonal rings do not delocalize over the whole molecule. A spherical fullerene of "n" carbon atoms has "n" pi-bonding electrons, free to delocalize. These should try to delocalize over
10376316
Osmium tetroxide


soccer ball model of buckminsterfullerene, a 60 atom carbon allotrope. The adduct, formed from a derivative of OsO, was C(OsO)(4-"tert"-butylpyridine). The adduct broke the fullerene's symmetry, allowing for crystallization and confirmation of the structure of C by X-ray crystallography. OsO is highly poisonous, even at low exposure levels, and must be handled with appropriate precautions. In particular, inhalation at concentrations well below those at which a smell can be perceived can lead to pulmonary edema and subsequent death. Noticeable symptoms can take hours to
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Aggregated diamond nanorod


, the test only works properly with a tip made of harder material than the sample being tested due to cracking. This means that the true value for nanodiamond is likely lower than 310 GPa. ADNRs (hyper diamonds / nano diamonds) are produced by compressing fullerite powder—a solid form of allotropic carbon fullerene—by any of two somewhat similar methods. One uses a diamond anvil cell and applied pressure ~37 GPa without heating the cell. In another method, fullerite is compressed to lower pressures (2–20 GPa) and then
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Superdense carbon allotropes


Superdense carbon allotropes are proposed configurations of carbon atoms that result in a stable material with a higher density than diamond. Few hypothetical carbon allotropes denser than diamond are known. All these allotropes can be divided at two groups: the first are hypothetically stable at ambient condition; the second are high-pressure carbon allotropes which become quasi-stable only at high pressure. According to the SACADA database, the first group comprises the structures, called hP3, tI12, st12, r8, I41/a, P41212, m32, m32
16726296
Fullerene


prediction. Around 1980, Sumio Iijima identified the molecule of C60 from an electron microscope image of carbon black, where it formed the core of a particle with the structure of a "bucky onion". In 1985 Harold Kroto of the University of Sussex, working with James R. Heath, Sean O'Brien, Robert Curl and Richard Smalley from Rice University, discovered fullerenes in the sooty residue created by vaporising carbon in a helium atmosphere. In the mass spectrum of the product, discrete peaks appeared corresponding to molecules with the exact mass
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Allotropes of carbon


allotropes can be achieved, including endohedral particles composed of predominantly amorphous carbon, carbon nanotubes, epitaxial graphene, nanocrystalline diamond, onion-like carbon, and graphitic ribbons, barrels, and horns. These structures exhibit high porosity and specific surface areas, with highly tunable pore diameters, making them promising materials for supercapacitor-based energy storage, water filtration and capacitive desalinization, catalyst support, and cytokine removal. Lonsdaleite is a hexagonal allotrope of the carbon allotrope diamond, believed to form from graphite present in meteorites upon their impact to
8634483
Carbon group


2003, is called graphene, and is in the form of a layer of carbon atoms arranged in a honeycomb-shaped formation. Silicon has two known allotropes that exist at room temperature. These allotropes are known as the amorphous and the crystalline allotropes. The amorphous allotrope is a brown powder. The crystalline allotrope is gray and has a metallic luster. Tin has two allotropes: α-tin, also known as gray tin, and β-tin. Tin is typically found in the β-tin form, a silvery
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C70 fullerene


C fullerene is the fullerene molecule consisting of 70 carbon atoms. It is a cage-like fused-ring structure which resembles a rugby ball, made of 25 hexagons and 12 pentagons, with a carbon atom at the vertices of each polygon and a bond along each polygon edge. A related fullerene molecule, named buckminsterfullerene (C fullerene), consists of 60 carbon atoms. It was first intentionally prepared in 1985 by Harold Kroto, James R. Heath, Sean O'Brien, Robert Curl and Richard Smalley at Rice University. Kroto
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Allotropy


Allotropy or allotropism () is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as "allotropes" of the elements. Allotropes are different structural modifications of an element; the atoms of the element are bonded together in a different manner. For example, the allotropes of carbon include diamond (the carbon atoms are bonded together in a tetrahedral lattice arrangement), graphite (the carbon atoms are bonded together in sheets of a hexagonal lattice), graphene (single
1664893
Superdense carbon allotropes


*, t32, t32*, H-carbon and uni. Among them st12 carbon was proposed as far as 1987 in the work of R. Biswas et al. MP8, OP8, SC4, BC-8 and (9,0) carbon allotropes belong to the second group - they are hypothetically quasi-stable at the high pressure. BC-8 carbon is not only a superdense allotrope but also one of the oldest hypothetical carbon structure - initially it was proposed in 1984 in the work R. Biswas et al. The MP8 structure proposed in the
16726297
Q-carbon


Q-carbon (quenched carbon) is an allotrope of carbon, discovered in 2015, that is ferromagnetic, electrically conductive, and glows when exposed to low levels of energy. It is relatively inexpensive to make, and some news reports claim that it has replaced diamond as the world's hardest substance. As of 2018, only the discoverers themselves have reported successfully making Q-carbon. According to researchers, Q-carbon exhibits a random amorphous structure that is a mix of 3-way (sp) and 4-way (sp)
9084810
Carbon nanotube


" are covalently bonded to the outer sidewalls of the underlying carbon nanotube. This hybrid material has useful properties of both fullerenes and carbon nanotubes. In particular, they have been found to be exceptionally good field emitters. In composite materials, the attached fullerene molecules may function as molecular anchors preventing slipping of the nanotubes, thus improving the composite’s mechanical properties. A carbon peapod is a novel hybrid carbon material which traps fullerene inside a carbon nanotube. It can possess interesting magnetic properties with heating and irradiation. It can also be
5059852
Fullerene


MoS), long used as a graphite-like lubricant, tungsten (WS), titanium (TiS) and niobium (NbS). These materials were found to be stable up to at least 350 tons/cm (34.3 GPa). Below is a table of main closed carbon fullerenes synthesized and characterized so far, with their CAS number when known. Fullerenes with fewer than 60 carbon atoms have been called "lower fullerenes", and those with more than 70 atoms "higher fullerenes". In the table,
10376309
Carbon nanofoam


Carbon nanofoam is an allotrope of carbon discovered in 1997 by Andrei V. Rode and co-workers at the Australian National University in Canberra. It consists of a cluster-assembly of carbon atoms strung together in a loose three-dimensional web. The material is extremely light, with a density of 2–10 mg/cm (0.0012 lb/ft). A gallon of nanofoam weighs about a quarter of an ounce. Each cluster is about 6 nanometers wide and consists of about 4000 carbon atoms linked in graphite-like sheets that
19823248
Fullerene


The resulting electric arc vaporizes the carbon into a plasma that then cools into sooty residue. Alternatively, soot is produced by laser ablation of graphite or pyrolysis of aromatic hydrocarbons. Combustion is the most efficient process, developed at MIT. These processes yield a mixture of various fullerenes and other forms of carbon. The fullerenes are then extracted from the soot using appropriate organic solvents and separated by chromatography. One can obtain milligram quantities of fullerenes with 80 atoms or more. C, C and C are available commercially. Fullerenes have been
10376329
Carbon


carbon nanofoam is a ferromagnetic allotrope discovered in 1997. It consists of a low-density cluster-assembly of carbon atoms strung together in a loose three-dimensional web, in which the atoms are bonded trigonally in six- and seven-membered rings. It is among the lightest known solids, with a density of about 2 kg/m. Similarly, glassy carbon contains a high proportion of closed porosity, but contrary to normal graphite, the graphitic layers are not stacked like pages in a book, but have a more
5059407
Fullerene chemistry


rule (IPR). The next homologue C has 24 IPR isomers of which several are isolated and another 51,568 non-IPR isomers. Non-IPR fullerenes have thus far only been isolated as endohedral fullerenes such as TbN@C with two fused pentagons at the apex of an egg-shaped cage. or as fullerenes with exohedral stabilization such as CCl and reportedly CH. Fullerenes with less than 60 carbons do not obey isolated pentagon rule (IPR). Because of the molecule's spherical shape the carbon atoms are highly pyramidalized, which
14980701
Nanotechnology


year. Second, Fullerenes were discovered in 1985 by Harry Kroto, Richard Smalley, and Robert Curl, who together won the 1996 Nobel Prize in Chemistry. C was not initially described as nanotechnology; the term was used regarding subsequent work with related graphene tubes (called carbon nanotubes and sometimes called Bucky tubes) which suggested potential applications for nanoscale electronics and devices. The discovery of carbon nanotubes is largely attributed to Sumio Iijima of NEC in 1991, for which Iijima won the inaugural 2008 Kavli Prize in Nanoscience. The basis for
1763918
Noble gas


form clathrate hydrates, where the noble gas is trapped in ice. Noble gases can form endohedral fullerene compounds, in which the noble gas atom is trapped inside a fullerene molecule. In 1993, it was discovered that when , a spherical molecule consisting of 60 carbon atoms, is exposed to noble gases at high pressure, complexes such as can be formed (the "@" notation indicates He is contained inside but not covalently bound to it). As of 2008, endohedral complexes with helium, neon, argon, krypton
1233468
Carbon peapod


another SWNT, thus creating a double-wall carbon nanotube. Owing to the ease with which fullerenes can encapsulate or be doped with other molecules and the transparency of nanotubes to electron beams, carbon peapods can also serve as nano-scale test tubes. After fullerenes containing reactants diffuse into an SWNT, a high-energy electron beam can be used to displace carbon atoms and induce high reactivity, thus triggering formation of C dimers and merging of their contents. Additionally, due to the enclosed fullerenes being limited to only a one
10125725
Filamentous carbon


during coke formation on reactor tubes and catalysts. The allotrope has the ability to destroy catalyst support structures, thus blocking reactors. It also forms during stream reforming, along with other varieties of carbon. Filamentous carbon can also be synthesized by cracking methane. The product is then gasified by hydrogen. In the experiment that discovered this, a nickel particle was used as the metal particle for the filament. The filament precipitates on the nickel particle's "support side". Filamentous carbon can also form when acetylene decomposes on films of
21449306
Allotropes of carbon


of The Carborundum Company, Manchester, UK. He had set out to develop a polymer matrix to mirror a diamond structure and discovered a resole (phenolic) resin that would, with special preparation, set without a catalyst. Using this resin the first glassy carbon was produced. The preparation of glassy carbon involves subjecting the organic precursors to a series of heat treatments at temperatures up to 3000 °C. Unlike many non-graphitizing carbons, they are impermeable to gases and are chemically extremely inert, especially those prepared at very
8634478
Carbon


hexagonal cells only, some of the cells of which fullerenes are formed may be pentagons, nonplanar hexagons, or even heptagons of carbon atoms. The sheets are thus warped into spheres, ellipses, or cylinders. The properties of fullerenes (split into buckyballs, buckytubes, and nanobuds) have not yet been fully analyzed and represent an intense area of research in nanomaterials. The names "fullerene" and "buckyball" are given after Richard Buckminster Fuller, popularizer of geodesic domes, which resemble the structure of fullerenes. The buckyballs
5059405
Nonmetal


. Many nonmetals have less stable allotropes, with either nonmetallic or metallic properties. Graphite, the standard state of carbon, has a lustrous appearance and is a fairly good electrical conductor. The diamond allotrope of carbon is clearly nonmetallic, however, being translucent and having a relatively poor electrical conductivity. Carbon is also known in several other allotropic forms, including semiconducting buckminsterfullerene (C). Nitrogen can form gaseous tetranitrogen (N), an unstable polyatomic molecule with a lifetime of about one microsecond. Oxygen is a diatomic molecule in
13626154
Allotropes of carbon


, according to the Samara Carbon Allotrope Database (SACADA). Diamond is a well known allotrope of carbon. The hardness and high dispersion of light of diamond make it useful for both industrial applications and jewelry. Diamond is the hardest known natural mineral. This makes it an excellent abrasive and makes it hold polish and luster extremely well. No known naturally occurring substance can cut (or even scratch) a diamond, except another diamond. The market for industrial-grade diamonds operates much differently from its gem-grade counterpart.
8634457
Robert Curl


Curl and his colleagues were at the time unaware of this. Later experiments confirmed their proposed structure, and the team moved on to synthesize endohedral fullerenes that had a metal atom inside the hollow carbon shell. The fullerenes, a class of molecules of which buckminsterfullerene was the first member discovered, are now considered to have potential applications in nanomaterials and molecular scale electronics. Robert Curl's 1985 paper entitled "C60: Buckminsterfullerine", published with colleagues H. Kroto, J. R. Heath, S. C. O’Brien, and R. E. Smalley,
6273649
Thomas Ebbesen


and Marie Curie University in Paris in the field of photo-physical chemistry. He then worked at the Notre Dame Radiation Laboratory before joining the NEC Fundamental Research Laboratories in Japan in 1988 where his research shifted first to novel carbon materials such as fullerenes (C), graphene and carbon nanotubes. After discovering how to mass-produce carbon nanotubes, he and his colleagues measured many of their unique features such as their mechanical and wetting properties. For his pioneering and extensive contribution to the field of carbon nanotubes, he shared the
6226743
Fullerene chemistry


" while the chemistry of carbon nanotubes is covered in carbon nanotube chemistry. Fullerene or C is soccer-ball-shaped or "I" with 12 pentagons and 20 hexagons. According to Euler's theorem these 12 pentagons are required for closure of the carbon network consisting of "n" hexagons and C is the first stable fullerene because it is the smallest possible to obey this rule. In this structure none of the pentagons make contact with each other. Both C and its relative C obey this so-called isolated pentagon
14980700
Nanocar


a gold surface, the molecules attach themselves to the surface via their fullerene groups and are detected via scanning tunneling microscopy. One can deduce their orientation as the frame length is a little shorter than its width. Upon heating the surface to 200 °C the molecules move forward and back as they roll on their fullerene "wheels". The nanocar is able to roll about because the fullerene wheel is fitted to the alkyne "axle" through a carbon-carbon single bond. The hydrogen on the neighboring carbon is no great
17755420
Toxicology of carbon nanomaterials


There has been much research on the nanotoxicology of fullerenes and carbon nanotubes. A review of works on fullerene toxicity by Lalwani et al. found little evidence that C is toxic. The toxicity of these carbon nanoparticles varies with dose, duration, type (e.g., C, C, M@C, M@C), functional groups used to water-solubilize these nanoparticles (e.g., OH, COOH), and method of administration (e.g., intravenous, intraperitoneal). The authors recommended that the pharmacology of each fullerene- or metallofullerene-
3771487
Superdense carbon allotropes


work J. Sun et al., is almost two times denser than diamond - its density is as high as 7.06 g/cm and it is the highest value reported so far. All hypothetical superdense carbon allotropes have dissimilar band gaps compared to the others. For example, SC4 is supposed to be a metallic allotrope while st12, m32, m32*, t32, t32* have band gaps larger that 5.0 eV. These new materials would have structures based on carbon tetrahedra, and represent the densest of such structures. On the
16726298
Carbon


are fairly large molecules formed completely of carbon bonded trigonally, forming spheroids (the best-known and simplest is the soccerball-shaped C buckminsterfullerene). Carbon nanotubes (buckytubes) are structurally similar to buckyballs, except that each atom is bonded trigonally in a curved sheet that forms a hollow cylinder. Nanobuds were first reported in 2007 and are hybrid buckytube/buckyball materials (buckyballs are covalently bonded to the outer wall of a nanotube) that combine the properties of both in a single structure. Of the other discovered allotropes,
5059406
Rhondite


to 2.25 percent carbon by weight. They are formed by mixing a high carbon and low carbon steel, such that the mixture as a whole has the desired carbon content. The mixture is then heated to a temperature at which the high carbon steel will melt, but kept below the melting point of the low carbon steel (~2750 F). The mixture is slightly cooled then maintained for time sufficient for the carbon present to form fullerenes and fullerene chains (approximately 15 minutes), and finally allowed to cool to room temperature
6155363
Fullerene


. Similar constraints exist if the fullerene has heptagonal (seven-atom) cycles. Open fullerenes, like carbon nanotubes and graphene, can consist entirely of hexagonal rings. In theory, a long nanotube with ends joined to form a closed torus-like sheet could also consist entirely of hexagons. Since each carbon atom is connected to only three neighbors, instead of the usual four, it is customary to describe those bonds as being a mixture of single and double covalent bonds. So-called endohedral fullerenes have ions or small
10376314
Dodecahedrane


was the simplest real carbon-based molecule with full icosahedral symmetry. Buckminsterfullerene (), discovered in 1985, also has the same symmetry, but has three times as many carbons and 50% more atoms overall. The synthesis of the C fullerene in 2000, from brominated dodecahedrane, may have demoted to second place. The angle between the C-C bonds in each carbon atom is 108°, which is the angle between adjacent sides of a regular pentagon That is quite close to the 109.5°, the angle between
3637974
Carbon nanobud


strong. In one more additional study that was done, it was discovered that each of the nanobud samples contained oxygen. The research, development, and manufacture of flexible and transparent electronics relies on novel materials, or materials which are mechanically flexible, lightweight and relatively low cost. These materials must also be conductive and optically transparent. Due to their close relation to the carbon nanotube family, carbon NanoBuds offer all of those traits, as well as more due to their inclusion of fullerene. Esko Kauppinen, a professor and researcher
5352624
Endohedral hydrogen fullerene


Endohedral hydrogen fullerene (H@C) is an endohedral fullerene containing molecular hydrogen. This chemical compound has a potential application in molecular electronics and was synthesized in 2005 at Kyoto University by the group of Koichi Komatsu. Ordinarily the payload of endohedral fullerenes are inserted at the time of the synthesis of the fullerene itself or is introduced to the fullerene at very low yields at high temperatures and high pressure. This particular fullerene was synthesised in an unusual way in three steps starting from pristine C fullerene: cracking open the carbon framework, insert hydrogen
8721456
C70 fullerene


, as the scientists were aiming to produce carbon plasmas to replicate and characterize unidentified interstellar matter. Mass spectrometry analysis of the product indicated the formation of spheroidal carbon molecules. In 1990, K. Fostiropoulos, W. Krätchmer and D. R. Huffman developed a simple and efficient method of producing fullerenes in gram and even kilogram amounts which boosted fullerene research. In this technique, carbon soot is produced from two high-purity graphite electrodes by igniting an arc discharge between them in an inert atmosphere (helium gas). Alternatively, soot is produced
14910102
Selective chemistry of single-walled nanotubes


Selective chemistry of single-walled nanotubes is a field in Carbon nanotube chemistry devoted specifically to the study of functionalization of single-walled carbon nanotubes. Reactivity of fullerene molecules with respect to addition chemistries is strongly dependent on the curvature of the carbon framework. Their outer surface (exohedral) reactivity increases with increase in curvature. In comparison with fullerene molecules single-walled nanotubes (SWNTs) are moderately curved. Consequently, nanotubes are expected to be less reactive than most fullerene molecules due to their smaller curvature, but more reactive than
15446163
Carbon


smelt even more iron: with sulfur to form carbon disulfide and with steam in the coal-gas reaction: Carbon combines with some metals at high temperatures to form metallic carbides, such as the iron carbide cementite in steel and tungsten carbide, widely used as an abrasive and for making hard tips for cutting tools. The system of carbon allotropes spans a range of extremes: Atomic carbon is a very short-lived species and, therefore, carbon is stabilized in various multi-atomic structures with different molecular configurations called allotropes.
5059398
Allotropes of carbon


most common allotropes of carbon. Unlike diamond, graphite is an electrical conductor. Thus, it can be used in, for instance, electrical arc lamp electrodes. Likewise, under standard conditions, graphite is the most stable form of carbon. Therefore, it is used in thermochemistry as the standard state for defining the heat of formation of carbon compounds. Graphite conducts electricity, due to delocalization of the pi bond electrons above and below the planes of the carbon atoms. These electrons are free to move, so are able to
8634463
Silicon


temperatures that decompose upon warming. Some silicon analogues of [[imine]]s, with a Si=N double bond, are known: the first found was BuSi=N–SiBu, which was discovered in 1986. [[File:SiC p1390066.jpg|thumb|right|Silicon carbide]] [[Silicon carbide]] (SiC) was first made by [[Edward Goodrich Acheson]] in 1891, who named it carborundum to reference its intermediate hardness and abrasive power between [[diamond]] (an allotrope of carbon) and [[
7347477
Carbon nanobud


the higher reactivity of the attached fullerene molecules, the hybrid material can be further functionalized through known fullerene chemistry. Additionally, the attached fullerene molecules can be used as molecular anchors to prevent slipping of the nanotubes in various composite materials, thus modifying the composite’s mechanical properties. Owing to the large number of highly curved fullerene surfaces acting as electron emission sites on conductive carbon nanotubes, nanobuds possess advantageous field electron emission characteristics. Randomly oriented nanobuds have already been demonstrated to have an extremely low work function for field electron emission. Reported
5352612
Allotropes of carbon


so strong. Although graphite is the most stable allotrope of carbon under standard laboratory conditions (273 or 298 K, 1 atm), a recent computational study indicated that under idealized conditions ("T" = 0, "p" = 0), diamond is the most stable allotrope by 1.1 kJ/mol compared to graphite. Graphite, named by Abraham Gottlob Werner in 1789, from the Greek γράφειν ("graphein", "to draw/write", for its use in pencils) is one of the
8634462
Allotropes of sulfur


The element sulfur exists as many allotropes. In terms of large number of allotropes, sulfur is second only to carbon. In addition to the allotropes, each allotrope often exists in polymorphs, delineated by Greek prefixes (α, β, etc.). Furthermore, because elemental sulfur has been an item of commerce for centuries, its various forms are given traditional names. Early workers identified some forms that have later proved to be single or mixtures of allotropes. Some forms have been named for their appearance, e.g. "mother
12018803
Chalcogen


bonded together in a bent formation. There is also an allotrope called tetraoxygen, or O, and six allotropes of solid oxygen including "red oxygen", which has the formula O. Sulfur has over 20 known allotropes, which is more than any other element except carbon. The most common allotropes are in the form of eight-atom rings, but other molecular allotropes that contain as few as two atoms or as many as 20 are known. Other notable sulfur allotropes include rhombic sulfur and monoclinic sulfur. Rhombic sulfur is the
6127386
Allotropes of carbon


or by mechanical exfoliation (repeated peeling) from graphite. Its applications may include replacing silicon in high-performance electronic devices. With two layers stacked, bilayer graphene results with different properties. Graphenylene is a single layer carbon material with biphenylene-like subunits as basis in its hexagonal lattice structure. It is also known as biphenylene-carbon. AA'-graphite is an allotrope of carbon similar to graphite, but where the layers are positioned differently to each other as compared to the order in graphite. Amorphous carbon is the name used for
8634470
Fullerene


double bonds" and are shorter than the 6:5 bonds (between a hexagon and a pentagon). Its average bond length is 1.4 angstroms. Another fairly common fullerene has empirical formula , but fullerenes with 72, 76, 84 and even up to 100 carbon atoms are commonly obtained. The smallest possible fullerene is the dodecahedral . There are no fullerenes with 22 vertices. The number of different fullerenes C grows with increasing "n" = 12, 13, 14, ..., roughly in proportion to "n" . For
10376301
Carbon peapod


Carbon peapod is a hybrid nanomaterial consisting of spheroidal fullerenes encapsulated within a carbon nanotube. It is named due to their resemblance to the seedpod of the pea plant. Since the properties of carbon peapods differ from those of nanotubes and fullerenes, the carbon peapod can be recognized as a new type of a self-assembled graphitic structure. Possible applications of nano-peapods include nanoscale lasers, single electron transistors, spin-qubit arrays for quantum computing, nanopipettes, and data storage devices thanks to the memory effects and superconductivity of nano
10125721
Carbon nanobud


walled CNTS can be weakened to prevent the formation of tight bundles of CNTs. Carbon nanobuds can be used as molecular support to prevent slipping of the matrix in composite materials and to increase the mechanical strength of them. The stability of CNBs is dependent on the type of carbon-carbon bond that is dissociated in the cycloaddition reaction. It has been shown that carbon atoms of the SWCNT near the fullerene C molecule were pulled outward from the original wall surface due to the covalent bonding with cycloaddition reaction between the fullerene and nanotube;
5352618
Fullerene


families of fullerenes, with fairly distinct properties and applications: the closed buckyballs and the open-ended cylindrical carbon nanotubes. However, hybrid structures exist between those two classes, such as carbon nanobuds — nanotubes capped by hemispherical meshes or larger "buckybuds". Buckminsterfullerene is the smallest fullerene molecule containing pentagonal and hexagonal rings in which no two pentagons share an edge (which can be destabilizing, as in pentalene). It is also most common in terms of natural occurrence, as it can often be found in soot. The
10376299