9Be and 31P NMR analyses on Be2+ complexation with cyclo-tri-μ-imidotriphosphate anions in aqueous solution

► Stability constants of ML, ML2 and M2L (L = cP3O6(NH)3) complexes have been evaluated from the peak area ratio of the deconvoluted 9Be NMR spectra. ► Formation of complexes coordinating with the nitrogen atoms of the cyclic framework in the cP3O6(NH)3 molecule has been excluded. ► The coexistence of the complexes is expected to produce a Be2+ ion bridged polymerized structure.