Site-selective valence isomerism as a unified electronic trigger for magnetism, chirality, and catalysis in Ni–carboxylate MOFs

] chains, reinforcing ferrimagnetic order and enhancing net magnetization. Concomitantly, the short-wavelength circular dichroism signals invert, and the oxygen-evolution overpotential decreases by ~100 mV. These results establish valence isomerism as an electronic trigger that coherently couples magnetic, chiroptical and catalytic properties in MOFs, offering a general design principle for multifunctionality in reticular materials.