Structures and solvation effects of [Fe(CO2)n]− cluster anions

We present infrared photodissociation spectra of [Fe(\chem{CO_2})$_{n}$]$^{-}$ ($n=3-7$) cluster anions. We use density functional theory to compare calculated vibrational frequencies to our experimental spectra to determine plausible structures for the molecular charge carriers. The spectra display similar characteristics to those of other complexes of first-row transition metals with \chem{CO_2} ligands, and show signatures of several structural motifs