Proton affinities of fluoro derivatives of benzene, toluene, and m-xylene from ab initio MP2 calculations

The proton affinity (PA) energies of fluoro derivatives of benzene, toluene . and m-xylene were obtained from ab initio MP2-FC/6-31G* calculations and compared with experimental results. Protonated forms of the molecules, resu lting from different ways of proton addition, were studied. Relative concen trations of isomeric arenonium ions were calculated and compared with the r esults of NMR studies on arenonium ions in solutions.