Zr12-acetate ligand exchange The Zr12-acetate cluster (200 mg, 1.4 mmol acetate, 1 eq.) was weighed into a 20 mL vial. The incoming carboxylic acid (1.5 equivalents) was added together with 1 mL of DCM and stirred for 60 min, after which a clear solution is obtained. Subsequently, the solution was further stirred under vacuum at 70 °C for 1 hour.