Reactivity of NO with small transition metal clusters II. Possible reaction mechanisms

Through extended Huckel (EHMO) calculations, we followed six possible reaction paths for the formation of Co2NO'+ and co4NO'+, whose stable structures were discussed in the previous paper of this series. The adduct formation enthalpy (DELTA hf) and the global hardness (n) have been calculated in order to establish the more probable structures and the more probable routes of reaction for the chemisorption of NO on Co'+x (x=2-4). It is shown that the maximum hardness principle, at the EHMO level, produces more realistic geometries. (Author) 11 refs