We have studied the formation of [Me2Al(OMTS)] [16,6] in fluorobenzene medium and have explored transition structures for both Me -abstraction and Me2Al + cleavage from the stable 16,6 4-C sheet or a higher energy i-16,7 precursor, respectively in gas phase. Those studies indicate that the lowest energy pathway involves Me -abstraction from Me3Al-OMTS by sheet 16,6 to form this outer-sphere ion pair. Here, we compare those results with smaller MAO sheets, though we note that only 6,4 seems to operate by the same mechanism. We also study 26,9 and the formation of [Me2Al(OMTS)] [26,8] as well as 16,6 and [Me2Al(OMTS)] [16,6] not only at M06-2X/TZVP level but also single point RI-MP2 calculations at the M06-2X/TZVP geometry. The results are summarized in Table .