For this reason, graphite conducts electricity along the planes of carbon atoms, but does not conduct in a direction at right angles to the plane. ChemDoodle Web Components allow the wielder to present publication quality 2D and 3D graphics and animations for chemical structures, reactions and spectra. The delocalized electrons are free to move throughout the plane. The ChemDoodle Web Components library is a pure JavaScript chemical graphics and cheminformatics library derived from the ChemDoodle application and produced by iChemLabs. Each carbon atom contributes one electron to a delocalized system of electrons that is also a part of the chemical bonding. In graphite, each carbon atom uses only 3 of its 4 outer energy level electrons in covalently bonding to three other carbon atoms in a plane. The movement of electrons is restricted and diamond does not conduct an electric current. For instance, in the sketcher above, the query structure defines any molecule with a benzene ring where a halogen (x) is ortho to a saturated oxygen, sulfur or selenium atom and para to a 3 membered chain where the second bond is either a single or double bond and is contained in no rings. In diamond all four outer electrons of each carbon atom are 'localized' between the atoms in covalent bonding. This means that the electrons are free to move throughout the structure, and gives rise to properties such as conductivity. Metallic structure consist of aligned positive ions ( cations) in a "sea" of delocalized electrons. An example attempting the Fridel-Crafts alkylation of benzene with 1-chloro-2-methylpropane the carbocation rearranges to a tert-butyl group stabilized by hyperconjugation, a particular form of delocalization.ĭelocalized electrons also exist in the structure of metals. One, an expected chemical reaction may not occur because the electrons delocalize to a more stable configuration, resulting in a reaction that happens at a different location. In Valence Bond Theory, delocalization in benzene is represented by resonance structures.Īnother example of a delocalized electrons can be found in a carboxylate group, wherein the negative charge is centered equally on the two oxygen atoms.ĭelocalized electrons are important for several reasons. The fact that the six C-C bonds are equidistant is one indication of this delocalization. In the simple aromatic ring of benzene the delocalization of six π electrons over the C 6 ring is often graphically indicated by a circle.
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