Cerocene

Cerocene is a organometallic complex with the chemical formula Ce₂. It is a sandwich compound consisting of a central cerium atom and two cyclooctatetraenide rings.

Preparation

Cerocene can be prepared by reducing cerium 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 complex, theoretical and experimental analysis of the compound indicates that is more correctly described containing a Ce atom.

Cerocene is a known precursor for uranocene, U₂:
Cerocene is commonly confused with the compound triscerium.