Infrared photodissociation spectroscopy of small Fe+–(CO2)n and Fe+–(CO2)nAr clusters

Infrared photodissociation spectra of mass-selected Fe+–(CO2)n and Fe+–(CO2)nAr clusters are reported. Under low power conditions, Fe+–(CO2)n clusters evaporate one CO2 molecule, while at higher fluence multiphoton absorption leads to the loss of multiple ligands. Photodissociation spectra show a blue-shift of the CO2 asymmetric stretch within the complexes which decreases with cluster size. Fe+–(CO2)nAr clusters fragment by the loss of argon. Their spectra appear at the same frequencies as those for the corresponding pure Fe+–(CO2)n clusters, but with significantly narrower linewidths. The IR bands observed suggest specific structures for each of these complexes.