Infrared Matrix-Investigations of the Interaction of Oxygen with Iron Atoms and Aggregates

Abstract

IR absorption investigations are reported of the reactivity of Fen (n = 1,2, ...) with mol. O2 in low temp. Ar matrixes. Besides the known .nu.O-O IR line of iron peroxide Fe(O2) at 956 cm-1 the band at .apprxeq.873 cm-1 which has been reported for FeO becomes strong at higher Fe concns. So far the occurrence of FeO has only been reported when at. O is formed in the device or at the matrix surface, e.g. by the reaction of O2 with excited rare-gas atoms from a hollow-cathode discharge. In this case also O3 lines have been reported. As no O3 lines are seen, it is believed that Fe2 is capable of O-O bond rupture resulting in a reaction product of 2 FeO. A new band grows at moderate Fe concn. at the expense of Fe(O2). It is assigned to the .nu.O-O mode of a FeO2Fe mol. A band at 1098 cm-1 is attributed to Fe(O2)2.