Nuclear magnetic resonance

27Al nuclear magnetic resonance (NMR) has been employed to study the structure of aqueous aluminum nitrate solutions in the presence of phenylphosphonic acid, potassium dihydrogen phosphate and phosphoric acid. Evidence has been obtained which indicates that in aqueous solution, aluminum ions can be complexed with phosphonate or phosphate in either a 1:1 or 2:1 molar ratio, respectively. The relative percentages of these complexes in solution are shown to be dependent on the ratio of aluminum nitrate to phosphonate or phosphate as well as the degree of ionization of the phosphorus species.

Group IVB metallocene polymers and oligomers undergo a pi-sigma rearrangement of the cyclopentadienyl moieties in DMSO based on NMR data. The sigma-Cp rings are stereochemically rigid at room temperature.