Multinuclear 3d-4f complexes with sandwichlike molecular structures are formed with the Schiff-base ligand bis(3-methoxysalicylidene)ethylene-1,2-phenylenediamine(H(2)L). The stoichiometry and structures are dependent on the Zn:Nd ratio and counteranions present. They are trinuclear [Nd(ZnL)2(NO3)2(H2O)2].NO3.EtOH.H2O (1), [Nd(ZnL)2Cl2(H2O)3].Cl.2MeOH.5H2O (2), and tetranuclear [Nd2(ZnL)2Cl6(MeOH)2].MeOH (3). Dinuclear complex [NdZnL(NO3)3MeCN].MeCN (4) was also characterized. Near-infrared (NIR) lanthanide luminescence is observed in these complexes.

Reaction of 1,4-benzenedicarboxylic acid (1,4-H2BDC) with EuCl(3).6H2O in MeOH in the presence of Et3N and MeCN gives a mixture of the 3-D metal-organic-framework (MOF) materials [Eu2(1,4-BDC)3(MeOH)4].8MeOH (1) and 2-D [Eu(1,4-BDC)(MeOH)4].Cl.MeOH.0.25H2O (2). Similar reactions afforded the isomorphous Gd (3) and Tb (4) analogs of 2. Reaction of 1,4-H2BDC with Ln(NO3)(3).6H2O under similar conditions gave [Ln(BDC)NO3(MeOH)2].MeCN.H2O (Ln = Eu (5) and Gd (6)), which have 2-D framework structures. The structures of 1-6 were determined by single crystal X-ray crystallographic studies and the luminescence properties of 1 and 4 in DMF solution were determined.

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A variety of Schiff base ligands have been synthesized in an effort to study the coordination chemistry of these ligands when reacted with various metal salts. By varying the structural features of the ligand as well as the synthetic route used to make the corresponding metal complexes, a number of different structural motifs have been observed. Schiff base ligands were chosen due to their ease of synthesis as well as their ability to bind a variety of metal salts. These complexes serve as model systems for and precursors to monomers for the preparation of conducting metallopolymers. Further functionalization of the Schiff base ligand with bithiophene end groups has resulted in electropolymerizable monomers. When polymerized these monomers give conducting metallopolymers which can then be used for a variety of applications. The products were characterized by multinuclear NMR, UV-Vis, and IR spectroscopy, and mass spectrometry. Solid-state structures were determined by single crystal X-ray diffraction studies. Electropolymerization yielded novel conducting polymers with embedded metals.