SPECTROSCOPIC AND THEORETICAL-STUDIES ON A 3-IRON CLUSTER WITH LINEARARRANGEMENT

The linear trinuclear iron complex Fe-3(SPh)(6)(CO)(6) with bridging b enzenethiolate ligands is the subject of temperature- and field-depend ent Mossbauer studies. The results reveal the two terminal iron atoms to be diamagnetic (Fe(II) and the central iron atom to be high-spin Fe (II). The magnetic Mossbauer pattern of the latter is dominated by a p ositive (!) internal field. Complementary to the experimental studies, also theoretical studies are performed. Local density molecular orbit al and ligand-field calculations yield an orbitally degenerate ground state that accounts for the unusual electronic and spectroscopic prope rties.