graphene carbon molecule 1

(above) graphene molecule showing pi orbitals #7.

Graphene consists of carbon atoms arrayed in a hexagonal pattern in a large sheet (see graphics of graphene drawn as simple spherical atoms). Layers of graphene constitute graphite, the familiar "lead" in pencils. Nanotubes are, in a sense, tubular graphene.

The electrons in each carbon atom are arranged in different orbitals. Two electrons occupy the inner spherical 1S shell. Then 2S and 2P accommodate the remaining four electrons. In a molecule, 2S and 2P are modified to create a hybridized SP2 bonding orbital. This has three equal lobes pointing outwards in a a plane and connecting to adjacent carbon atoms (pinkish sausage like connecting bodies in this diagram see our graphene bonds only graphic). The fourth electron in this outer shell occupies a pi orbital that projects above and below the molecular plane (transparent yellow lobes). This pi orbital merges with adjacent pi orbitals creating a huge orbital which allows easy movement of electrons across the plane of the molecule. This is what gives graphene its remarkable electrical conductivity.

The Nobel prize (The 2010 Nobel Prize in Physics - Press Release) has just been awarded for graphene. See our 3D anaglyph of graphene.

Graphene images on this page are 600 pixels across, the originals are at least 4096 pixels across.

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