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Two unsymmetrical ditopic hexadentate ligands designed for simultaneous recognition of two different trivalent lanthanide ions are synthesized. In a pair of different lanthanide ions in acetonitrile solution, the ligand [L.sup.AB3] shows selectivity and gives high yields of heterobimetallic complexes.

Three different polymers containing the N,N',N''-chelate ligand tris[2-(1-vinylimidazolyl)]phosphine are prepared. All three polymeric Cu complexes are found to efficiently promote the hydrolysis of activated phosphoesters with the relative activity being dependent on the nature of the polymer and the substrate.

Research has been conducted on the molecular LiF and LiFHF complexes. The synthesis of these complexes has been carried out via the use of the metallamacrocyclic receptors and the structural and spectroscopic features of the isolated LiF and LiFHF ion pairs are described.

Research has been conducted on the tetraazamacrocyclic ligands. The design of these ligands constructed with the aim to sensitize luminescence of terbium(III) and europium(III) ions in water is described.

Research has been conducted on the complexation of Ln(III) ions by the meso-octaethylporphyrinogen. Isolation and structural characterization of Ln-porphyrinogen complexes are described.

The bonding between d2-vanadium(III) and calix[4] arene oxosurface was presented. It was shown that the reaction between the two compounds results to a dimer, in which vanadium(III) attains pentacoordination, when a coordinating solvent is absent. Extension of the Huckel analysis reveals that vanadium diazomethane bonding can be attained through three main orbital interactions which illustrate the high bond order of the vanadium-nitrogen bond.

Lanthanide cluster complexes with a high and controlled nuclearity are reported. Initial photophysical investigation indicates that nonradiative deactivation processes are minimized, resulting in a sizable quantum yield for the Eu(super III) edifice.

The synthesis of lanthanide complexes with a new series of tridentate ligands based on benzimidazole-substituted 8-hydroxyquinolines and the luminescent properties of the corresponding [La.sup.III] and [Nd.sup.III] chelates is described. The ligands could be used to design luminescent materials incorporating near-infrared emitting lanthanides or metal centers with square-planar ([Pt.sup.II], [Pd.sup.II]) and octahedral ([Zn.sup.II], [Ru.sup.II], [Os.sup.II], [Ir.sup.III]) coordination environment.

The isomerization of N,N-trans-mer-heteroleptic iridium complex to a more stable cis-mer-isomer observed during the preparation of vacuum-processed organic light-emitting devices (OLEDs) and reproduced in solution is described. The mixture of isomers could be used to prepare polymer-based devices, which could find application as an emitter of better purity.

The preparation of cylindrical nanostructures from the reaction of a tripodal ligand containing terminal 2,3-dihydroxypyridine groups with (arene)ruthenium(II) complex is described. The complexes form a molecular cylinder with two terminal (arene)ruthenium trimers, which act as the connecting end groups for two ligands.

A study report describes the use of bidentate carboxylate ligands to develop novel RAPTA complexes with properties similar to those of related platinum species. The new complexes showed a similar order of activity in inhibiting cancer cell-growth proliferation (as determined by in vitro assays) and exhibited oligonucleotide binding characteristics (as evidenced by matrix-assisted laser desorption ionization mass spectrometry) similar to those of the RAPTA precursor.

A series of coordination polymers containing Group I or II metal ions, connected through an imidazolium-centered dicarboxylate ligand, are isolated from water and characterized by single crystal X-ray diffraction. The results have shown that all the structures incorporate water molecules that adopt a range of different structural motifs.

The crystal structure of a strontium-imidazolium polymeric material obtained from the reaction of zwitterionic 1,3-bis(carboxymethyl)-imidazolium with SrCO3 (2:1) in water is reported. The two-dimensional polymer is separated by water sheets in which the water molecules form near-planar hexagons.

The reaction of [(Et(sub 3)P)PdCl(sub 2)](sub 2) with 2,3-dihydroxypyridine, 5-chloro-2,3-dihydroxypyridine, or 2-hydroxynicotinic acid in the presence of base gives neutral, metallomacrocyclic compounds in which the heterocycles act as bridging ligands. The macrocycles contain four or ten palladium atoms as witnessed by single crystal X-ray analyses.

The nature of P-N and P=N bonds is extensively explained. The protonation of diphosphinoamines attached to pyridine at the ortho-position quantitatively affords the corresponding iminobiphosphines isomers. The starting material can be recovered quantitatively by deprotonation with base.

A series of imidazolium salts with the nitrile functional group attached to the alkyl side chain are prepared and characterized using spectroscopic methods. It is found that these ionic liquids could act as both solvent and ligand for catalyzed reactions, and this application is demonstrated in hydrogenation reactions.

The reaction of [(arene)RuCl2](sub 2) (arene= cymene, 1,3,5-C6H3Me3) and [Cp*RhCl2](sub 2) half-sandwich complexes with tridentate heterocyclic ligands in the presence of base is investigated. All complexes are formed in a highly diastereoselective fashion.

The experiment conducted to study the preparation of Ditopic hexadentate ligands is presented. It is designed to recognize and insert heteropairs of lanthanide ions through a thermodynamically controlled self-assembly process into functional triple helicate assemblies.

Research has been conducted on 12-metallacrown-3 complexes. The authors report that the Mulliken charges of these complexes have been investigated via a single point analysis at the HF level.

Research has been conducted on CO) (sub)3 Re (super)I (H (sub)2 O) (sub)3] (super)+. The authors report the results of kinetic investigation of the water exchange process on this compound carried out via the use of (super)17 O NMR.

Research has been conducted on aminophosphine with electron-withdrawing nitrile group. The authors describe the preparation of this compound from the lithiation od 2-aminobenzonitrile and the addition of Ph (sub)2 PCl.

Oxygen-17 NMR spectroscopy is used to study the water exchange on Ru(CO)(H2O)(sub 5)(super 2+) and cis-Ru(CO)(sub 2)(H2O)(sub 4)(super 2+) as a function of the temperature, and on fac-Ru(CO)(sub 3)(H2O)(sub 3)(super 2+) as a function of the acid concentration. X-ray crystal structures of Ru(CO)(H2O)(sub 5)(super 2+) and cis-Ru(CO)(sub 2)(H2O)(sub 4)(super 2+) are determined and a comparison of different ground-state properties with the observed reactivities is made.