STUDIES ON RARE-EARTH COMPLEXES WITH CROWN ETHERS .25. SYNTHESIS, CHARACTERIZATION, AND STRUCTURE OF THE COMPLEXES OF LANTHANIDE NITRATES WITH 13-CROWN-4

The lanthanide nitrate complexes with 13-crown-4(13-C-4) have been prepared in AcOEt. These new complexes with the general formula Ln(NO3)3.(13-C-4) (Ln = La-Nd, Sm-Lu) have been characterized by means of elemental analysis, IR and H-1-NMR spectra, conductivity measurements, and TG-DTA techniques. The crystal and molecular structure of Nd(NO3)3 . (13-C-4) has been determined by single crystal X-ray diffraction. It crystallizes in the monoclinic space group P2(1)/a with Z = 8. Lattice parameters are a = 15.393(1), b = 12.578(1), c = 19.279(2) angstrom, beta = 113.05(1)-degrees, V = 3435 angstrom3, D(c) = 2.01 g cm-3, D(o) = 2.03 g cm-3, mu = 31.0 cm-1(MoK(alpha)), F(000) = 2056. The structure was solved by Patterson and Fourier techniques and refined by least-squares to a final conventional R value of 0.032 for 5218 independent reflections with I greater-than-or-equal-to 3sigma(I). There are two independent Nd(NO3)3 . (13-C-4) monomers in one asymmetrical unit. The coordination numbers are ten in these two independent monomers.