Broken symmetry density functional study of biomimetic models for Purple Acid Phosphatases of the type Fe(III)-M(II) (MÂ =Â Fe, Cu, Ni, Co and Mn)

► Fe(III)-M(II) (M = Fe, Cu, Ni, Co and Mn) biomimetic compounds for PAP. ► DFT broken symmetry formalism predicts weak antiferromagnetic coupling. ► Correlation with M(II)-bridge distance. ► TPSSh functional predicts accurate magnetic coupling constants. ► All complexes show one magnetic exchange σ/π pathway.