1989 Symmetry 2  
The uniqueness of C--C bonds, which allows life to exist and gives birth to the infinite number of organic compounds, is analysed. A brief survey of the two known C allotropes, graphite and diamond, stresses how the different structure of the nets leads to such enormous differences in properties. The synthesis of diamond is surveyed. Other possible, hypothetical forms of elemental carbon are mathematically surveyed depending on the hybridization state of the C atoms, i.e. on the vertex degrees
more » ... the vertex degrees in the infinite lattice. Related nets with other atoms instead of carbon are mentioned. Then the symmetry of hydrocarbons having C skeletons that are fragments from the graphite net (benzenoid hydrocarbons) or from the diamond lattice (diamond hydrocarbons) is discussed, and the connection between symmetry and molecular stability is noted.
doi:10.1016/b978-0-08-037237-2.50033-7 fatcat:rgef5nrdzzbbfjdwoqxjxqjlie