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Protonation behavior of the geometrical isomeric pair cis- and trans-[Co(ade-kN9)Cl(en)2] were examined and the crystal structures were determined by x-ray analysis.

Research has been conducted on the chromium(III) and nickel(II) imino nitroxide complexes with different beta-diketonates. The synthesis, structural and magnetic characteristics and optical properties of these complexes have been examined and the details are presented.

Research has been conducted on the inorganic or/and organic molecule assemblies. The use of polyoxovanadate as a structural building block in the hydrogen bonded inorganic-organic three-dimensional structure synthesis is described.

Correlation between 1H and 2H NMR contact of radical nickel(II) complexes and the exchange coupling constant J has been studied. The analysis was carried out to derive a new method for determining the J value from the NMR spectra. Results show that the C-H contact shifts of the radical complexes result from the antiferromagnetic interaction between nickel(II) ion and NIT2-py radical. Two C-D NMR contact shifts could be distinguished from the NIT2-py SOMO.

The successful synthesis of a range of novel 3d-4f heterodinuclear compounds ((acac)(sub2)Cr(ox)Ln(HBpz(sub3))(sub2)) is reported. The crystal structure of complex Yb is emphasized. Metal-metal interactions between Cr(III) and Ln(III) are shown to be weak in magnetic interaction, although they are strong on the basis of energy transfer.

The synthesis and characterization of three Cr(III)-edda-type complexes coordinated by pzdc are presented. The pyrazole-3,5-dicarboxylato (pzdc) chromate(III) complexes contain linear tetradentate ethylenediamine-N,N'-diacetate, trimethylenediamine-N,N'-diacetate or ethylenediamine-N,N'-dipropionate. The complexes were characterized by elemental analyses, column chromatography, 2H NMR, FAB mass spectra and X-ray spectra.

Circularly polarized luminescence (CPL) and circular dichroism of cesium tetrakis(3-heptafluoro-butyryl-(+)-camphorato) Eu(III) complexes in EtOH and CH[Cl.sub.3] solutions are examined. The CPL activity is found to be constant and large due to chiral square antiprism eight coordination (SAPR-8) in the solution.

The structural characterization of Na[La((+)-hfbc)4]-CH3CN in both the solid state and in solution with respect to configurational chirality are reported. The X-ray crystal analysis of sodium tetrakis(3-heptafluorobutylryl-(+)-camphorato) Ln(III) complexes has revealed an unprecedented pseudo-achiral dodecahedron, whereas in CHCl3 solution, the exciton circular dichroism (CD) and NMR spectra have showed a novel chiral delta-SAPR-8 configuration which is stereospecifically formed by a trapped [Na.sup.+] ion with [Na.sup.+]...FC (fluorocarbon) interactions.

Photolysis of Cp*Ir(2-Spy)(N(sub 3)) (1) gave a pyridine-1-imido-2-thiolato complex, Cp*Ir(1-N-2-Spy) (2) as a result of N-atom insertion into the Ir-N(py) bond. Compound 2 was reacted with CH(sub 3)I to afford the N-methylated product, [Cp*Ir(1-NMe-2-Spy)]I (3).

The [Fe(super II)(H3L)](BF4)(super 2).3H2O complex is synthesized, where H3L (tris{[2-imidazole-4-yl)methylidene}amino]-ethyl}amine is a tripodal ligand obtained by condensation of tris(2-aminoethyl)amine and 4-formylimidazole (fim) in a 1:3 molar ratio. A supramolecular approach inducing strongly cooperative spin crossover behavior is reported.

Research has been conducted on ruthenium(II) complexes with 8-(dimethylphosphino)quinoline (Me (sub)2 Pqn). The authors describe the sythesis of these complexes, and the analysis of their structural, electrochemical and spectroscopic properties.

A report is presented that was prepared to study the X-ray structure of the eddp complex Na[Cr(sub 2)(eddp)(Mu-pzdc)](1 dot)6H(sub 2)O(eddp=ethylenediamine-N,N'- dipropionate) was determined to have a (sum-cis)-(unsym-cis) geometrical configuration with intramolecular three-center hydrogen bonds. The report stated that a series of the pzdc-bridged Cr(III)complexes the anomalous conformations in two different geometrical configurations which could be entrapped due to steregnostic coordination through the intramolecular N-H(3 dots)O hydrogen bond interaction.

The synthesis and physical properties of two series of mixed-ligand NIT2-py nickel(II) complexes of (Ni(beta-diketonato)2(NIT2-py)) and (Ni-(beta-diketonato)(tmen)(NIT2-py))(super +) with various types of beta-diketonates have been studied. The magnetic behavior and electronic absorption spectra of the complexes were examined in relation to the coligand effect. Results show significant relation between the intensities of the formally spin-forbidden bands and those of the new metal-ligand charge-transfer elements based on the observed magnetic coupling.

Photolysis of the (azido)(pyridine-2-thiolato)iridium(III) complex Cp∗Ir(2-Spy)(N3) (1) gave a pyridine-l-imido-2-thiolato complex, Cp∗Ir(1-N-2-Spy) (2), in which one of the nitrogen atoms of the azide ligand has been inserted into the Ir-N(py) bond (Cp∗ = Β5-C5Me5). Complex 2 reacted quantitatively with methyl iodide to give the N-methylated product, [Cp∗Ir(1-NMe-2-Spy)]l (3). X-ray crystallography revealed that both 2 and 3 have similar two-legged piano stool structures with planar 1-N-2-Spy2- or 1-NMe-2-Spy- ligands, which form iridacyclopentadienyl-like rings by moderate S(pπ)/N(pπ) to Ir(dπ) π donation. [ABSTRACT FROM AUTHOR]

The reaction of Ln(III) ions with a tripodal ligand HBpz(3)(-) (hydrotris(pyrazol-1-yl)borate) and a "complex ligand" [Cr(acac)(2)(ox)](-) (acac(-) = acetylacetonate, ox(2)(-) = oxalate) in aqueous solution afforded a series of the novel 3d-4f heterodinuclear complexes [(acac)(2)Cr(ox)Ln(HBpz(3))(2)] (Ln = Eu (1), Gd (2), Tb (3), Yb (4), Lu (5)). The crystal structure of 4 has been determined by X-ray diffraction. Complex 4 crystallizes in monoclinic space group P2/n, of which the cell parameters are a = 8.594(3) Å, b = 18.538(4) Å, c = 12.093(2) Å, beta = 93.71(2) degrees, and Z = 2. The Yb atom has an eight-coordinate distorted square antiprismatic coordination geometry. The intramolecular Cr.Yb distance is 5.631(1) Å. The magnetic susceptibility data for complex 2 showed that the Cr(III)-Gd(III) interaction is weakly antiferromagnetic with an exchange coupling constant J(CrGd) = -0.09 cm(-)(1). The luminescence measurements demonstrated the energy transfers for both Ln(III) --> Cr(III) and Cr(III) --> Ln(III), of which the degree of emission quenching depends on the energy gap of the excited levels in two metal centers. These results reveal that the metal-metal interactions between Cr(III) and Ln(III) are very weak in magnetic interaction but are strong from the viewpoint of energy transfer.