Metallocenes and their use as catalyst component

The present invention relates to a polynuclear metallocene compound of the formula I. where M1 a tetravalent metal is, L1 are each independently the same or different and are a substituted cyclopentadienyl group, L2 and L3 are each independently the same or different and are a π-ligand, B are each independently the same or different and are each a divalent bridging unit, X are independently the same or different, and for a hydrogen atom, a halogen atom, a C1-C10-Fluorkohlenstoffrest or a hydrocarbon-containing radical having 1-40 carbon atoms, and k is an integer from 0 to 10. The metallocene compound of the invention is useful as a catalyst component for the production of olefin polymers.