Abstract
Fe(IV)=O biomimetic model complexes have been characterized using nuclear vibrational resonance spectroscopy (NRVS). Features and systematic trends in the low energy region reflect equatorial and axial bonding differences that relate to differences in reactivity. These trends have been computationally extended to predict the spectra of putative Fe(IV)=O intermediates in non-heme iron enzymes and show the utility of the NRVS method for structural insight.