Synthesis and Structure of the 2-Amino-3-Hydroxypyridine Complexes with Trivalent Praseodymium, Neodymium, Samarium, and Europium Nitrates: Crystal Structure of Tris(2-Amino-3-Hydroxypyridine)trinitratosamarium(III) Monohydrate

The complexes of the composition LnL3(NO3)3 · nH2O (Ln = Pr, Nd, Sm, Eu; n = 0-3) are prepared by the reaction of Ln(NO3)3 with 2-amino-3-hydroxypyridine (L) in acetone at pH 2. The crystal structure of SmL3(NO3)3 · H2O is determined. The ligand is involved in the complex as a neutral species of the bipolar ion coordinated through the oxygen atom. The IR and UV spectral parameters of the complexes are discussed.