Theoretical studies of the structure and stability of protonated olefins in the gas phase and in solution

The calculation of carbenium and carbonium type cations resulting from the protonation of olefins with growing length and increasing chain branching was carried out by quantum chemical methods which were tested elsewhere.One result is the distinction of olefins with an equal number of alkyl substituents on both sides of the double bond and other ones with different number. In the latter case generally no bridged structures could be defined.The influence of nucleophilic solvents on the stability of the cationic structures is simulated on the basis of Klopman's solvaton model. These calculations show that solvents may change the gas phase data in a remarkable way.