A process for polymerizing olefins is disclosed. The process uses an organometallic complex with at least one non-bridged indenoindolyl ligand bonded to M. The substituent on the indole nitrogen contains an atom selected from the group consisting of S, O, P, and N. Polyolefins from the process have unexpectedly high molecular weight compared with polyolefins made using similar supported indenoindolyl complexes.