Cyclopentadienyl complex

A cyclopentadienyl complex is a coordination complex of a metal and cyclopentadienyl groups (C
5
H
5
, abbreviated as Cp). Cyclopentadienyl ligands almost invariably bind to metals as a pentahapto (η5-) bonding mode. The metal–cyclopentadienyl interaction is typically drawn as a single line from the metal center to the center of the Cp ring.