Infrared spectrum and photochemistry of di-iron enneacarbonyl in matrices at 20 K: evidence for the formation of Fe2(CO)8

Abstract

The i.r. spectrum of Fe₂(CO)₉(D_3h) in matrices at 20 K is reported. Irradiation with u.v. light very rapidly produces spectral changes; annealing the matrix to 30 K leads to further changes and prolonged photolysis gives a final spectrum which is unaffected by subsequent annealing. These changes are attributed to the formation of both bridged and unbridged forms of Fe₂(CO)₈ and the bonding in this system is briefly discussed. There is evidence for the formation of nitrogen-containing carbonyl species during photolysis in nitrogen matrices.