What is Cyclopentadienyliron dicarbonyl dimer?

Cyclopentadienyliron dicarbonyl dimer is an organometallic compound with the formula Fe2]2, often abbreviated to Cp2Fe24, 2]2 or even Fp2, with the colloquial name "fip dimer". It is a dark reddish-purple crystalline solid, which is readily soluble in moderately polar organic solvents such as chloroform and pyridine, but less soluble in carbon tetrachloride and carbon disulfide. Cp2Fe24 is insoluble in but stable toward water. Cp2Fe24 is reasonably stable to storage under air and serves as a convenient starting material for accessing other Fp 2] derivatives.