| prov:value
| - Also, it is possible to use, for the metallocene (h-3), a bridged metallocene in which at least two of R2, R3, R4 and R5 in the general formula (20), for example, R2 and R3, are a group (ligand) having a skeleton of cyclopentadienyl, wherein said at least two groups are bound together through a bridging group, such as an alkylene, substituted alkylene, silylene or substituted silylene.
|