Synthesis and vibrational spectroscopy of 57Fe-labeled models of [NiFe] hydrogenase: first direct observation of a nickel--iron interaction.

A new route to iron carbonyls has enabled synthesis of 57Fe-labeled [NiFe] hydrogenase mimic (OC)3 57Fe(pdt)Ni(dppe). Its study by nuclear resonance vibrational spectroscopy revealed Ni--57Fe vibrations, as confirmed by calculations. The modes are absent for [(OC)3 57Fe(pdt)- Ni(dppe)]+, which lacks Ni--57Fe bonding, underscoring the utility of the analyses in identifying metal--metal interactions. [ABSTRACT FROM AUTHOR]