Cerocene is a organometallic complex with the chemical formula Ce(C<sub>8</sub>H<sub>8</sub>)<sub>2</sub> (Ce(cot)<sub>2</sub>). It is a sandwich compound consisting of a central cerium atom and two cyclooctatetraenide rings.
Cerocene can be prepared by reducing cerium(III) di-cyclooctatraene anion salts:
Cerocene decomposes when exposed to water or oxygen to yield non-stoichiometric cerium-oxides and cyclooctratraene derivitives.
It undergoes a disproportionation, leading to an equilibrium between cerocene and a double-decker structure containing two cerium atoms:
Although the cyclooctatetraenide ligand is usually considered a dianion and therefore cerocene is identified as a Ce(IV) complex, theoretical and experimental analysis of the compound indicates that is more correctly described containing a Ce(III) atom.
Cerocene is a known precursor for uranocene, U(C<sub>8</sub>H<sub>8</sub>)<sub>2</sub>:
Cerocene is commonly confused with the compound tris(cyclopentadienyl)cerium.