Catalyst comprising a metallocene complex and a co-catalyst

The invention relates to a metallocene complex according to formula I or II wherein M is a metal selected from lanthanides or transition metals from group 3, 4, 5 or 6 of the Periodic System of the Elements, Q is an anionic ligand to M, k is the no. of Q groups and equals the valence of M minus 2, R is a divalent bridging group, R1, R2, R3 and R4 are each independently chosen from the group consisting of hydrogen (H)​; a halogen atom; a silyl, alkyl, cycloalkyl, aryl, alkylaryl or arylalkyl group; and R5, R6, R7 and R8 are each independently chosen from the group consisting of hydrogen (H)​; a halogen atom; a silyl, alkyl, cycloalkyl, aryl, alkylaryl or arylalkyl group; or two adjacent radicals R5 and R6, R6 and R7, and R7 and R8 are connected with each other in a hydrocarbon ring system. The invention also relates to a catalyst comprising the metallocene complex, to a process for making polyolefins and to the use of the polyolefins for making articles