Reactive Structures of Hydrocarbons and Catalytic Hydrogenation

Abstract

A CARBON atom in its ground-state has the structure 1s22s22p2, 3P. In such a state, the spins of the p electrons are coupled to unity. Penney1 has shown that in order to obtain a divalent carbon atom, that is, one in which the spins are free, a mixture of the 1D and 3P states in the ratio 1 : 3 must be considered. The energy of attaining such a structure is the promotional energy. Such a structure has no independent existence, but arises from a perturbation of the carbon atom by the atom with which it is going to form a bond.