CRYSTAL-STRUCTURES OF THE COMPLEXES OF RARE-EARTH PICRATES WITH N,N,N',N'-TETRAPHENYL-3,6-DIOXAOCTANEDIAMIDE

The complexes oi rare earth picrate with N, N, N', N'-tetraphenyl-3, 6 -dioxaoctanediamide (TDD), [Eu(pic)(3)(TDD)]. 2CH(3)CN and [Y(pic)(3)( TDD)], have been synthesized. The crystal structures reveal that TDD a cts as a tetradentate ligand, forming a ring-like coordination structu re with its oxygen atoms together with one oxygen atom oi the bidentat e picrate. In the Eu(III) complex, the europium ion with a larger ioni c radius lies our of the ring, while in the Y(III) complex, the yttriu m ion with a smaller ionic radius enters the cavity of the ligand. The structures of the complexes are greatly affected by the ionic radii d ue to participation of the picrates in coordination.