GAS-PHASE GENERATION AND STRUCTURAL CHARACTERIZATION OF THE FE(CO2)+ CLUSTER

The hitherto unknown Fe(CO2)+ cluster is conveniently available by ion-molecule reactions of ''bare'' Fe+ with beta-butyrolactone in the gas phase. By using the technique of Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, collision-induced dissociation and ligand exchange experiments are conducted and the results suggest an Fe+-(CO2) structure for the cluster with a bond dissociation energy of 8 +/- 2 kcal/mol. While this small binding energy is advantageous for using the Fe(CO2)+ cluster as an ideal precursor to generate other interesting Fe+ complexes, as expected all attempts failed to bring about an Fe+-mediated coupling of CO2 and RH (R = H, CH3) to the corresponding carbonic acids.