Abstract: Bridged and unbridged fluorenyl-containing metallocenes of the formula R″x(FlRn)(CpRm)MQk wherein Fl is a fluorenyl radical, Cp is a cyclopentadienyl, indenyl, tetrahydroindenyl, or fluorenyl radical, each R is an organo radical, R″ is a structural bridge linking (FlRn) and (CpRm), M is a metal selected from the group consisting of IVB, VB, and VIB metals, each Q is selected from the group consisting of hydrocarbyl or hydrocarbyloxy radicals and halogen, x is 1 or 0, k is an integer sufficient to fill out the remaining valences of M, n is in the range of 0 to 7, and m is 0 to 7, further characterized by the fact that if (CpRm) is unsubstituted fluorenyl and metallocene is an unbridged metallocene, then n is 1 to 7 and if R″ is 1,1-dimethylmethylene and (CpRm) is unsubstituted cyclopentadienyl or 3-methylcyclopentadienyl, then n is 1 to 7.

Abstract: Double bound metallocenes, i.e. metallocenes having a cyclopentadienyl-containing radical that is bound to a transition metal both by a pi bond and by a sigma carbon bond of a substituent of that same cyclopentadienyl-containing radical can be prepared by reducing metallocenes having a cyclopentadienyl-containing radical having at least one an unsaturated substituent. Also a process for producing polymers comprising contacting at least one olefinic monomer under suitable polymerization conditions with such double bound metallocenes.