Comparison of the experimental geometric structural parameters of α-O from NRVS/EXAFS to other mononuclear Fe(IV)=O intermediates [bTAML (18), TMC (6, 28, 29), N4Py (6, 30, 31), and TMG3tren (5, 16, 32)]. Fe, tan; O, red; N, blue; TBP, trigonal bipyramidal.