Buckminsterfullerene does not exhibit "superaromaticity": that is, the electrons in the hexagonal rings do not delocalize over the whole molecule. The sp3-hybridized carbon atoms Other atoms can be trapped inside fullerenes to form inclusion compounds known as endohedral fullerenes. Fullerenes are sparingly soluble in many solvents. Common solvents for the fullerenes include aromatics, such as toluene, and others like carbon disulfide.
Solutions of pure buckminsterfullerene have a deep purple color. Solutions of C70 are a reddish brown. Fullerenes are the only known allotrope of carbon that can be dissolved in common solvents at room temperature. In , researchers from the University of Vienna demonstrated that wave-particle duality applied to molecules such as fullerene.
Science writer Marcus Chown stated on the CBC radio show Quirks and Quarks in May that scientists are trying to make buckyballs exhibit the quantum behavior of existing in two places at once. Quantum mechanics Some fullerenes e.
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C76, C78, C80, and C84 are inherently chiral because they are D2-symmetric, and have been successfully resolved. This was the highest transition temperature for a molecular superconductor.
Since then, superconductivity has been reported in fullerene doped with various other alkali metals The Tc observed is Organic Photovoltaics OPV 2. Fullerenes are powerful antioxidants, reacting readily and at a high rate with free radicals, which are often the cause of cell damage or death.
Fullerenes hold great promise in health and personal care applications where prevention of oxidative cell damage or death is desirable, as well as in non-physiological applications where oxidation and radical processes are destructive food spoilage, plastics deterioration, metal corrosion. Polymer Additives Fullerenes and fullerenic black are chemically reactive and can be added to polymer structures to create new copolymers with specific physical and mechanical properties.
They can also be added to make composites. Much work has been done on the use of fullerenes as polymer additives to modify physical properties and performance characteristics. Catalysts Marked ability to accept and to transfer hydrogen atoms; hydrogenation and hydrodealkylations. Highly effective in promoting the conversion of methane into higher hydrocarbons. Inhibits coking reactions.
Journal of computational chemistry 20 1 , , Journal of the American Chemical Society 2 , , Chemistry—A European Journal 8 17 , , The Journal of Physical Chemistry B 39 , , Journal of the American Chemical Society 23 , , Journal of the American Chemical Society 24 , , Angewandte Chemie International Edition in English 31 3 , , Journal of chemical theory and computation 3 6 , , Chemistry—A European Journal 7 20 , , This follows from the fact that a spherical species having a same-spin half-filled last energy level with the whole inner levels being fully filled is also aromatic.
In organic chemistry, spherical aromaticity is formally used to describe an unusually stable nature of some spherical compounds such as fullerenes, polyhedral boranes. In , Andreas Hirsch and coworkers in Erlangen, Germany, formulated a rule to determine when a fullerene would be aromatic. Two different resonance forms of benzene top combine to produce an average structure bottom In organic chemistry, aromaticity is a property of cyclic ring-shaped , planar flat structures with a ring of resonance bonds that gives increased stability compared to other geometric or connective arrangements with the same set of atoms.
Aromatic molecules are very stable, and do not break apart easily to react with other substances. Organic compounds that are not aromatic are classified as aliphatic compounds—they might be cyclic, but only aromatic rings have special stability low reactivity. Since the most common aromatic compounds are derivatives of benzene an aromatic hydrocarbon common in petroleum and its distillates , the word aromatic occasionally refers informally to benzene derivatives, and so it was first defined.
Nevertheless, many non-benzene aromatic compounds exist. An aromatic funct. Doering , although several authors were using this form at around the same time. Aromatic compounds are more stable than. Model of the C60 fullerene buckminsterfullerene. Model of the C20 fullerene. Model of a carbon nanotube. C60 fullerite bulk solid C 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 formula C, often written Cn, where n is the number of carbon atoms.
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However, for some values of n there maybe more than one isomer. The family is named after buckminsterfullerene C , the most famous member, which in turn is named after Buckminster Fuller. The closed fullerenes, especially C, are also informally called buckyballs for their obvious resembl. Look up custard apple in Wiktionary, the free dictionary. Custard apple: fruiting branch with sections of fruit and seeds Custard apple is a common name for a fruit, and the tree which bears it, Annona reticulata. The size ranges from 7 centimetres 2. When ripe, the fruit is brown or yellowish, with red highlights and a varying degree of reticulation, depending again on the variety.
The flesh varies from juicy and very aromatic to hard with a repulsive taste. The custard apple is native to the New World, but has been found on the island of Timor in Indonesia as early as C. Carbonyl iron is a highly pure It usually has the appearance of grey powder, composed of spherical microparticles. Most of the impurities are carbon, oxygen, and nitrogen. BASF invented carbonyl iron powder in  and claims to be the world's leading producer. Carbonyl iron became the first magnetic recording oxide although quickly replaced in by iron oxide.
In electronics, carbonyl iron is used to manufacture magnetic cores for high-frequency coils and in production of some ferrites. Spherical particles manufactured of carbonyl iron are used as a component of the radar absorbing materials used by the military, in stealth vehicles, for example. Other uses are in powder metallurgy, metal injection molding, and in various specialty products.
Powdered cores ma. Metallic bonding is a type of chemical bonding that rises from the electrostatic attractive force between conduction electrons in the form of an electron cloud of delocalized electrons and positively charged metal ions. It may be described as the sharing of free electrons among a structure of positively charged ions cations. Metallic bonding accounts for many physical properties of metals, such as strength, ductility, thermal and electrical resistivity and conductivity, opacity, and luster.
For example, elemental gallium consists of covalently-bound pairs of atoms in both liquid and solid state—these pairs form a crystal structure with metallic bonding between them. History As chemistry developed into a science it became clear that metals formed the large majority of the periodic table of the elements and great progr. Artemisia cina, commonly known as santonica zahr el shieh el -khorasani , Levant wormseed, and wormseed, is an Asian species of herbaceous perennial in the daisy family.
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The powder is grayish-green in colour with an aromatic odour and a bitter taste. Dysphania ambrosioides is another plant with the common name wormseed, called epazote in Mexican cuisine. It is native to China, Kazakhstan, and Kyrgyzstan. The essential oil is largely composed of 1,8-cineole, but contains a wide variety of other com.
Flowers Pterocaulon sphacelatum is a species of flowering plant in the Asteraceae family. It is found only in Australia, where it is known as "Fruit-salad Plant" or "Applebush", as well as other Aboriginal names. Description Its natural habitat is subtropical dry continental grasslands.
It has spherical pinkish flowerheads.
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This plant is relatively common in Alice Springs. During the later part of Classical Antiquity, in Koine Greek final centuries BC , its pronunciation shifted to that of a voiceless labiodental fricative. It may be that phi originated as the letter qoppa and initially represented the sound before shifting to Classical Greek. As with other Greek letters, lowercase phi is used as a mathematical or scientific symbol. Use as a symbol. Both graphene and fullerene bear resemblance in having sp2 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 presence of exclu. Goldberg polyhedron 3,1 and geodesic polyhedron 3,1. The Goldberg polyhedra and geodesic polyhedra were precursors to the Goldberg-Coxeter operation. The Goldberg—Coxeter construction or Goldberg—Coxeter operation GC construction or GC operation is a graph operation defined on regular polyhedral graphs with degree 3 or 4.
The GC construction can be thought of as subdividing the faces of a polyhedron with a lattice of triangular, square, or hexagonal polygons, possibly skewed with regards to the original face: it is an extension of concepts introduced by the Goldberg polyhedra and geodesic polyhedra. The GC construction is primarily studied in organic chemistry for its application to fullerenes, but it has been applied to nanoparticles, computer-aided design, basket weaving, and the general study of graph theory and polyhedra. Artemisia absinthium wormwood, grand wormwood, absinthe, absinthium, absinthe wormwood is a species of Artemisia native to temperate regions of Eurasia and Northern Africa and widely naturalized in Canada and the northern United States.
Description Artemisia absinthium is a herbaceous perennial plant with fibrous roots.
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The stems are straight, growing to 0. Dysphania pumilio is a species of flowering plant in the amaranth family known by the common name clammy goosefoot. It is native to Australia, but it can be found in other parts of the world as an introduced species, often growing in disturbed and waste areas such as roadsides and lots. The leaves are alternately arranged, up to 2 centimeters long, lance-shaped to oval and edged with bumpy lobes. The surface of the leaf is coated in white sticky glands and sparse hairs. The inflorescence is a spherical cluster of densely packed tiny green flowers located in the leaf axils.
Each flower is pebbly with glands and covers the developing fruit. References Rahiminejad, M. Liquidambar formosana, commonly known as the Chinese sweet gum or Formosan gum, is a species of tree in the family Altingiaceae native to East Asia. Description Liquidambar formosana is a large, native, deciduous tree that grows up to m tall. Roots can be aggressive and branches are usually covered with corky projections. The individual flowers of L.
However, both sexes can be found in the same plant. It requires moist soil and can grow in li. Crinum asiaticum, commonly known as poison bulb, giant crinum lily, grand crinum lily, spider lily, is a plant species widely planted in many warmer regions as an ornamental. It is a bulb-forming perennial producing an umbel of large, showy flowers that are prized by gardeners.
All parts of the plant are, however, poisonous if ingested. Some reports indicate exposure to the sap may cause skin irritation. It has a leaf base formed pseudobulb is spherical, the upper part of the bulb is cylindrical, and the base is laterally branched, with a diameter of about cm. Leaves lanceolate, margin undulate, apically acuminate with 1 sharp pointed, dark green, up to 1 m long, width. Lindera benzoin commonly called spicebush, common spicebush, northern spicebush, wild allspice, or Benjamin bush is a shrub in the laurel family, native to eastern North America, ranging from New York to Ontario in the north, and to Kansas, Texas, and northern Florida in the center and south.
Within its native range it is a relatively common plant where it grows in the understory in moist, rich woods, especially those with exposed limestone. They have a smooth edge with no teeth and are dark green above and paler below. Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash. Along with sodium hydroxide NaOH , this colorless solid is a prototypical strong base. It has many industrial and niche applications, most of which exploit its caustic nature and its reactivity toward acids.
An estimated , to , tonnes were produced in KOH is noteworthy as the precursor to most soft and liquid soaps, as well as numerous potassium-containing chemicals. It is a white solid that is dangerously corrosive. Most commercial samples are ca. Consequently, KOH typically contains varying amounts of water as well as carbonates - see below. Its dissolution in water is strongly exothermic. Concentrated aqueous solutions are sometime. Azafullerenes are a class of heterofullerenes in which the element substituting for carbon is nitrogen.
They can be in the form of a hollow sphere, ellipsoid, tube, and many other shapes. Spherical azafullerenes resemble the balls used in football soccer. Besides the pioneering work of a couple of academic groups, this class of compounds has so far garnered little attention from the broader fullerene research community. Many properties and structures are yet to be discovered for the highly-nitrogen substituted subset of molecules. It is a white, hygroscopic crystalline solid with a low melting point.
The point group of crown-6 is S. The dipole moment of crown-6 varies in different solvent and under different temperature. Borassus palmyra palm is a genus of five species of fan palms, native to tropical regions of Africa, Asia and New Guinea. The leaves are fan-shaped, 2—3 m long and with spines along the petiole margins no spines in B. The leaf sheath has a distinct cleft at its base, through which the inflorescences appear; old leaf sheaths are retained on the trunk, but fall away with time. All Borassus palms are dioecious, with male and female flowers on separate plants; male flowers are less than 1 cm long and in semi-circular clusters, sandwiched between leathery bracts in pendulous catkins; female flowers are 3—5 cm wide, globe-shaped and solitary, sitting directly on the surface of the inflorescence axis.
The fruits are 15—25 cm wide, roughly spherical and each contain large seeds. Matricaria discoidea Matricaria chamomilla Matricaria is a genus of flowering plants in the Chamomile tribe within the sunflower family. Most are very common in the temperate regions of Europe, Asia, and America, as well as in northern and southern Africa, and some are naturalised in Australia.