Crystal structures of two Sm^III complexes with dipicolinate [DPA]²⁻ ligands: comparison of luminescent properties of products obtained at different pH values

The formation of the two title compounds, Na 3 [Sm(DPA) ]·14H 2 O trisodium tris(pyridine-2,6-dicarboxylato-κ , N 6 )samarate(III) tetradecahydrate, [Sm(C 7 H NO 4 ) O, and catena -poly[[[diaqua(6-carboxypyridine-2-carboxylato-κ )samarium(III)]-μ-pyridine-2,6-dicarboxylato-κ : ] tetrahydrate], {[Sm(C )(C )(H O) ]·4H O} n depends on pH value adjusted with NaOH solution. In both crystal structures, coordination spheres Sm III cations were found to be best described by a tricapped trigonal prism (TTP), more regular donor set for than that [Sm(DPA)(HDPA)(H O. supramolecular features structures are dominated O—H...O hydrogen bonds between water molecules atoms dipicolinato ligands. Samples made from solutions at = 2, 5, 7, 10, crystals present in each sample ground powder. powder samples analyzed X-ray diffraction luminescence spectroscopy. splitting bands spectra recorded powders 77 K was observed vary pH.