SYNTHESIS AND CRYSTAL-STRUCTURE OF THE 2 2 COMPLEXES BETWEEN LIGHTER RARE-EARTH NITRATES AND N,N,N',N'-TETRAPHENYL-3,6-DIOXAOCTANEDIOICDIAMIDE/

The 2 : 2 complexes between lighter rare earth nitrates and N,N,N',N'- tetraphenyl-3,6-dioxaoctanedioicdiamide (TDD), [RE(TDD)(2)(H2O)(2)][RE (NO3)(6)]1-4 (1, 2, 3, 4 for RE = La, Ce, Pr, Nd, respectively) and [C e(TDD)(2)(H2O)(2)][Ce(NO3)(6)] . CH3OH . 2H(2)O 5, have been synthesiz ed and characterized. The crystal structure of 5 reveals that TDD acts as a tetradentate forming a half-ring coordination structure. There i s a little difference in the conformations of the two TDDs. The Ce ion s are 10- and 12-coordinated for the complex cation and anion, respect ively, and the coordination polyhedrons are a bicapped distorted squar e antiprism and a distorted icosahedron, respectively.