Polysubstituted cyclopentadiene-containing compound, in which at least one substituent is has the formula --RDR'.sub.n, in which R is a linking group between the cyclopentadiene and the DR'.sub.n group, D is a hetero atom selected from group 15 or 16 of the Periodic Table of Elements or an aryl group, in which case R has at least the length of an ethylene group, R' is a hydrocarbon radical containing 1-20 carbon atoms (e.g., alkyl, aryl, aralkyl,. and the like, including straight chain, branched, cyclic, and derivatives thereof, and n is the number of R' groups bound to D (note that the R' groups may be identical or different).