Thermodynamic investigations relevant to hydrogen atom transfer by the high-valent iron imido complex [(LFe)-Fe-Mes NAd]OTf have been undertaken. The complex is found to be weakly oxidizing by cyclic voltammetry (E-1/2 = -0.98 V vs Cp2Fe+/Cp2Fe in MeCN). A combination of experimental and computational studies has been used to determine the acidity of (LFe)-Fe-Mes-N(H)Ad(+)(pK(a) = 37 in MeCN), allowing the N-H BDFE (88(5) kcal/mol) to be calculated from a thermodynamic cycle. Consistent with this value. [(LFe)-Fe-Mes NAd]OTf reacts with 9,10-dihydroanthracene (C-H BDE = 78(1) kcal/mol) to form anthracene. anthracene.