Cp2Fe
Cp2Fe, also known as ferrocene, is an organometallic compound with the formula Fe(C5H5)2. It consists of a central iron atom sandwiched between two parallel cyclopentadienyl rings in an η5 coordination. The molecule is a classic example of a metallocene and is typically described as an 18-electron, Fe(II) complex. At room temperature the rings rotate rapidly about the Fe–Cp axis, making the molecule fluxional and giving rise to an average symmetry different from the instantaneous structure.
In terms of bonding, each cyclopentadienyl ring acts as a five-point, six-electron donor to iron, and together
Preparation of ferrocene typically involves the reaction of sodium cyclopentadienide with iron(II) salts (for example, iron(II)
Historical significance and applications: ferrocene's discovery in the early 1950s and its subsequent structural elucidation sparked