Iron carbonyls Mossbauer spectra

The compound now formulated as [(OC)3FePMe2Ph]3 was found to be a trinuclear species rather than di- or tetra-nuclear from the similarity of its Mossbauer spectrum to Fe3(CO)i2 [5]. All three iron atoms have shown a change in chemical isomer shift, and this leads one to suggest that one terminal carbonyl group on each iron atom has been substituted. This has since been confirmed by an X-ray crystal structure analysis [28]. 

Molecular rotation in the cavity has been discussed for many compounds using nmr(8,9), esr(lO) and Mossbauer spectroscopy(4,5). A complete description of the Mossbauer spectrum for such a case has been given by Gibb(4) for that of the 3 1 clathrate of thiocarbonyl diamide and bis( -cyclopentadienyl)iron(II). Evidence for conformational isomerism has been presented recently based on the ir spectra of y-cyclopentadienylmetal carbonyl complexes such as CpFe(CO) SiCl Me(ll), ip -MeC H Mn(CO) (P(OMe) )(12) and others(13), and on the Mossbauer... 

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