Editing Cyclopentadienyl complex (section)

==Examples==
''Bis''cyclopentadienyl complexes are called [[metallocene]]s. A famous example of this type of complex is [[ferrocene]] (FeCp<sub>2</sub>), which has many analogues for other metals, such as [[chromocene]] (CrCp<sub>2</sub>), [[cobaltocene]] (CoCp<sub>2</sub>), and [[nickelocene]] (NiCp<sub>2</sub>). When the Cp rings are mutually parallel the compound is known as a [[sandwich compound|sandwich]] [[coordination complex|complex]]. This area of [[organometallic chemistry]] was first developed in the 1950s.  Bent metallocenes are represented by compounds of the type [MCp<sub>2</sub>L<sub>x</sub>].  Some are catalysts for [[ethylene]] [[polymerization]].<ref>{{cite book|first=R. H. |last=Crabtree |date=2001 |title=The Organometallic Chemistry of the Transition Metals |edition=3rd |location=New York, NY|publisher= John Wiley & Sons}}{{ISBN missing}}</ref> Metallocenes are often thermally stable, and find use as [[catalyst]]s in various types of reactions.

Mixed-ligand Cp complexes containing Cp ligand and one or more other ligands.  They are more numerous. One widely studied example is the [[cyclopentadienyliron dicarbonyl dimer|Fp dimer]], (Cp<sub>2</sub>Fe<sub>2</sub>(CO)<sub>4</sub>). Monometallic compounds featuring only one Cp ring are often known as [[half sandwich compound]]s or as piano stool compounds, one example being [[methylcyclopentadienylmanganese tricarbonyl]] (CpMn(CO)<sub>3</sub>).