THE SYNTHESES CHARACTERIZATION AND CRYSTAL-STRUCTURE OF RARE-EARTH COMPLEXES WITH L-PROLIN

The complexes of Ln(L-Pro)s(H2O)2(ClO4)3(Ln = Pr, Nd and Er. L-Pro = L -Proline) were synthesized and characterized by elemental analysis, IR . spectra and thermal analysis. The singal crystal Pr2(L-Pro)6(H2O)4(C lO4)6 Was also obtained. The crystal belongs to monoclinic, P2(1), a = 0.9879 (3) nm, b = 2.1883 (4) nm, c = 1.3393 (2)nm, beta = 91.23(2)-d egrees, V = 2.895(1) nm3, Z = 2. R = 0.035 for 5032 observed reflectio ns. The coordination polyhedron of Pr(III) ion comprises six oxygen at oms from L-Pro molecules and two water molecules. Each L-Pro molecule coordinates to two Pr(III) ions through its carboxyl group which serve s as a bridging bidentate ligand to form onedimensional chain structur e.