The 14 Å octamethyloctahydrodibenzofluorene moiety has been incorporated into a sterically expanded constrained geometry catalyst, Me2Si (η 1-C29H36)(η1-Nt Bu) ZrCl2⊙ OEt2 (1). The solid-state structure suggests that the activated olefin polymerization catalyst is quite spatially accessible, rationalizing its extraordinary reactivity toward α-olefins. 1/MAO (MAO= methylaluminoxane) can be more reactive toward α-olefins than toward ethylene ...