Graphene Graphene Graphene is an allotrope (form) of carbon consisting of a single layer of carbon atoms arranged in a hexagonal lattice. It is a semimetal with small overlap between the valence and the conduction bands (zero bandgap material).<ref name="10.1002/adma.201502544 p.6519-6525"></ref> It is the basic structural element of many other allotropes of carbon, such as graphite, diamond, charcoal, carbon nanotubes and fullerenes. Graphene has many uncommon properties. It is the strongest material ever tested, conducts heat and electricity efficiently, and is nearly transparent. Graphene shows a large and nonlinear diamagnetism, greater than that of graphite, and can be levitated by neodymium
Carbon–carbon bond triple bond are 134 pm and 120 pm, respectively. Also a consequence of its severe steric congestion, hexakis(3,5-di-"tert"-butyl)ethane has a greatly elongated central bond with a length of 167 pm. On the other hand, a very short triple bond of 115 pm has been observed for the iodonium species [HC≡C–IPh][CFSO], due to the strongly electron-withdrawing iodonium moiety. Carbon–carbon bond A carbon–carbon bond is a covalent bond between two carbon atoms. The most common form is the single bond: a bond composed of two electrons, one from each of the two atoms. The carbon–carbon single bond is a sigma bond and