Theoretical study of ammonia oxidation on platinum clusters - Adsorption of ammonia and water fragments

► NH3 and H2O exhibit donor-acceptor bonds to platinum. ► OH, NH2, NH and N exhibit covalent bonds to platinum. ► N atoms are the cause of platinum poisoning during ammonia oxidation. ► Bending modes of adsorbed NH2 and H2O are blueshifted compared to free molecules. ► Correct shift in frequency was predicted in comparison with prior calculations.