Cyclopentadienyl anion
In chemistry, the cyclopentadienyl anion or cyclopentadienide is an aromatic species with a formula of [C5H5] and abbreviated as Cp. Its name derives from the molecule cyclopentadiene. Salts of the cyclopentadienyl anion can be stable, e.g., Sodium cyclopentadienide. more complex coordination compounds are known as cyclopentadienyl complexes, such as metallocene