Comparison periodic (left) and cluster model analysis (right) of CH4 hydroxylation by Fe(IV)=O centers in Fe-CHA, performed at the Adiabatic Connection Fluctuation−Dissipation Theorem in its Random Phase Approximation (blue) and PBE-D2 (red) levels of theory. Structures: A –reactant complex, B – H-atom transfer TS, C – CH3 radical first product, D – C-O bond formation TS, E – Fe-methanol adduct. Color legend: blue: Al; yellow: Si; red: O; gold: Fe. Reproduced from ref 117. Copyright 2016 American Chemical Society.