THE GAS-PHASE SOLVATION OF C2H5+, S-C3H7+, AND S-C4H9+ WITH CH4 - THE ISOMERIC STRUCTURES OF C2H5+ AND C2H5+...CH4

The gas-phase equilibria of the clustering reactions of C2H5+, s-C3H7+, and s-C4H9+ with CH4 were studied with a pulsed electron-beam high-pressure mass spectrometer. The bond energies of the clusters s-C3H7+ (CH4)n and s-C4H9+ (CH4)n are nearly n-independent. In contrast, there is an irregular decrease in the bond energies for the clusters C2H5+ (CH4)n between n = 1 and 2. It is found that the non-classical C2H5+ isomerizes to the classical one during the clustering reaction of C2H5+ with CH4 and the terminal methyl protonated propane is formed.