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A series of trinuclear [Ni.sub.2.sup.II][Ln.sup.III] complexes of 2,6-di(acetoacetyl)pyridine ([H.sub.2]L) (Ln = La-Lu except for Pm) are synthesized by a 'one-pot reaction' of [H.sub.2]L, Ni[(N[O.sub.3]).sub.2].6[H.sub.2]O and Ln[(N[O.sub.3]).sub.3].n[H.sub.2]O in methanol and their structures and magnetic properties are characterized. The results have shown that the [Ni.sup.II]-[Ln.sup.III] interaction is weakly antiferromagnetic for Ln = Ce, Pr, and Nd and ferromagnetic for Ln = Gd, Tb, Dy, Ho and Er.

A three-connector ligand containing three pyridyl groups as coordination sites and three amide groups as guest interaction sites (1,3,5-benzene triarboxylic acid tris[N-(4-pyridyl)amide] (4-btapa) is used to produce a new base-type catalytic pore framework. The results have shown that the combination of metal ions and designed organic ligand can provide porous coordination polymer (PCP) with functional organic sites (FOS) showing base catalytic performance.

The synthesis and crystallographic characterization of a series of flexible guest-binding coordination polymers generally formulated as [{[Cu[(bpetha).sub.2]].2P[F.sub.6]}.sub.n] is presented. The compound [{[Cu[(bpetha).sub.2][(acetone).sub.2].2P[F.sub.6]}.sub.n] easily releases its co-ordinated acetone guests by thermal treatment, forming the stable crystalline host compound [{[Cu[(bpetha).sub.2]].2P[F.sub.6]}.sub.n], capable of binding guests at the [Cu.sup.II] axial sites protected temporarily by the P[F.sub.6.sup.-] anions.

A strategy for observing regular assemblies of guest molecules to utilize the well-regulated one-dimensional (1D) channel of porous coordination polymers is presented. Obtaining crystal structures indicate that guest molecules are confined in a linear fashion to form crystalline-like regular ordered arrays, which are characteristic of the kind of gas molecules and the geometrical and potential properties of the ultramicropore.

The synthesis and crystallization procedure of two novel 3D supramolecualr network of of Cu(II), viz. [Cu(bipy)(1,4-napdc)(H(sub 2)O(sub 2))]n (1) and {[Cu(bpe)(sub 1.5)(1,4-napdc)](H(sub 2)O)}n(2) (bipy = 4, 4'-bipyridine; bpe = 1,2-bis(4-pyridyl)ethane; 1,4-napdc(super2-) = 4-naphthalenedicarboxylate) are presented. It is found that both the compounds crystallize by slow evaporation from the ammonical solution of the as-synthesized solid

Coordination compounds were synthesized and structurally characterized. It should be noted that the azpy ligand is a good candidate for the construction of new assembling systems of coordination compounds through its aromatic interactions.

A study on molecular structures and physicochemical properties of diruthenium complexes with ligand-unsupported Ru-Ru bonds is conducted by changing the countercation. The results demonstrate that the ligand-unsupported Ru-Ru bonds are essentially stabilized by the dianionic nature of the catecholate derivatives without any other bridging or supporting species.

Selective bond formation with the series of first-period transition metal ions is accomplished using the metalloligand L(super Cu) [Cu(2,4-pydca)(sub 2)](super 2-). New Cu(super II) metalloligand [Cu(2,4-pydca)(sub 2)](super 2-) L(super Cu) controlled bond formation for the first-period transition metal ions and magnetic properties.

Prussian blue (PB) nanoparticles protected by organic polymers such as poly(vinylpyrrolidone) (PVP) and poly(diallyldimethyammonium chloride) (PDDA) were prepared and different experimental conditions are investigated to control the size of the PB nanoparticles. Findings show that the PB nanoparticles with the PVP protection show high solubility in a variety of organic solvents and solvent-dependent CT absorption.

The relationships between the host structure of iron-chloranilate layers and the intercalated charged guests are described. Study shows that hydrogen-bond supported anionic layers based on iron-chloranilate mononuclear complexes can be used as inorganic hosts for the intercalation of guest cations to construct new types of multilayered inorganic-organic hybrid materials.

Research has been conducted on Cr (super)III (X (sub)4 SQ) (sub)3 where SQ= o-semiquinonate and X= Cl abd Br. The treatment of this compound with acetonitrile has been carried out and the results indicate that the compound undergoes a rapid ligand exchange reaction with the solvent molecules or the nitrogen-donor chelate reagents in polar solvents.

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.

A mechanism is proposed, which involves rate-determining addition of the carbene center of A to the remote alkynyl carbon of a second alkynlcarbene complex to generate vinyl carbene intermediate C, and rearrangement of C to the enediyne complex by a [1,1.5] Re shift. The tethered bis(alkynlcarbene) complexes 13 and 16 are studied to probe the geometric requirement for C=C bond formation.

A combination of framework-builder (Cu(II) ion and 4,4'-bipyridine (4,4'-bpy) ligand) and framework-regulator (AF6 type anions; A = Si, Ge, and P) provide a series of novel porous coordination polymers. The findings imply that the 4,4'bpy - bridged porous coordination polymers are suitable for the construction of not only the second-generation compounds but also the third generation compounds.

Research has been conducted on the mononuclear compounds. The synthetic reactions, structural characterization and physicochemical properties of these compounds have been investigated.

Research has been conducted on the helicity induction in zinc bilinone derivatives that bear chiral auxiliaries. The effect of solvents on this induction has been investigated via circular dichroic spectroscopy and (super)1 H NMR experiments.

Research discusses structural aspects of charge-transfer (CT) compounds of transition metal complexes that exhibit electrochemical reduction reactions. Data indicate that the redox state of the coordinated ligands determines the mixed-valence state of the chromium module of the CT compounds.

Results resolve the role of host-guest and solvation intermolecular interactions involved in zinc porphyrin receptors' recognition of amines and alpha-amino esters. Data further point out that the former interaction mediate binding selectivity in organic solvents whereas the latter drives binding in water.

Research is presented demonstrating the significant selectivity of receptors binding alpha-amino esters, oligopeptides and amines in water. All the receptors have a Lewis acidic site, a hydrophobic binding pocket and an electrostatic recognition site.

A study illustrates how the modification of heme-propionates improves the peroxidase activity of reconstituted myoglobin for small molecule substrates, which led to the engineering of a new binding domain on the myoglobin surface. The existing chemical mutation of the prosthetic group will function as a new strategy for synthesizing novel catalysts with tailored properties. Experimental methods and findings are presented.

A study was conducted to analyze helical chirality induction in the bilinone framework by the point chirality of the chiral auxiliary. A series of zinc bilinone derivatives supporting a chiral auxiliary at the helix terminal were determined to carry out the analysis. Results indicated the sensitivity of chiral induction to the distance to the asymmetric carbon and to substituents on the asymmetric carbon.

The valence-detrapping phase transition in a mixed-valence trinuclear iron cyanoacetate complex, (Fe3O(O2CCH2CN)6(H2O)3), was studied by 57Fe Mossbauer spectroscopy, calorimetry and X-ray crystallography. The lower molecular symmetry in the low-temperature valence-trapped phase than in the valence-detrapped phase was observed for the first time in these kinds of complexes. A voluntary molecular polarization was also seen in the valence-trapped phase.

The crystal structure of copper(II) intercalation compounds, ((Cu(CA)(H2O)2)(G))n, (H2CA = chloranilic acid, G = 2,5-dimethylpyrazine (1) and phenazine(2)) consists of one dimensional (Cu(CA)(H2O)2)m chains. The chains intercalate G1 molecules to form a stack while G2 molecules are linked to (Cu(CA)(H2O))n chain. The Cu-atom exhibits a six coordinate geometry having two bis-chelating CA2-ions and water molecules. This provides a linear coplanar chain structure. X-ray crystallography and magnetic susceptibility help to understand the structure of the complex .

The synthesis of a new copper(II) coordination polymer Cu(sub 2)(oxalate)(sub 2)(pyrazine)(sub 3)n reveals the crystallographic structure of the copper (II) units. The coordination polymer crystallizes in the triclinic space group and displays an extended sheet structure of copper(II) ions joined by oxalate anions and pyrazine. The recurring unit of the polymer contains two types of 4 + 2 coordination systems with O4N2. The Cu-ox-Cu-arrangement demonstrates a pleated ribbon, which shows that the planes of Cu-ox-Cu form a boat conformation.

The synthesis, molecular structure and characteristics of two- and three-dimensional copper halide complexes with (tetrakis(methylthio)tetrathiafulvalene) (TMT-TTF) are described. The copper(I) complexes, which were studied via single crystal x-ray diffraction techniques, were Cu2(mu-X)2(mu-TMT-TTF) infinity where (X = Cl,Br,I). When X = Cl, the result is a '2D sheet of TMT-TTF molecules arranged between zigzag frames of CuCl.

X-ray crystallographic studies of the dicopper(I) and disilver(I) compounds of 1,6-bis(diphenylphosphino)hexane, which constitute a novel macrocyclic system, indicate the presence of a cavity for the inclusion of tetrahedral and Y-shaped anions, suggesting that these anions exhibit host-guest type of reactions. The presence of a six methylene group-containing ligand enables the trapping of ions such as NO(sub 3)(super -) and ClO4. The distance between the two metal atoms in a molecule provides the cavity size.

Design of a two-dimensional sheet containing six-membered rings of metal ions, interlinked by aromatic ligands, involve an extremely-favored combination of three- or four-coordinate metal ions and ligands with 1,2, 5-thiadiazole and pyrazole frames. The ring frame, which divides the orientation of the aromatic ligand, can be deformed and the aromatic ligand between the sheets can be stacked because of the coordination of a specific counteranion to the metal ion.

The syntheses and characterizations of the complexes (Cu2(phz)3(MeOH)2)(phz)(PF6)2 (phz = phenazine), (Cu(phz)2(H2O))ClO4, (Cu(phz)2(NO3)), (Ag(phz)(NO3)2)infinity and (Ag2(phz)(NO3)2)infinity were reported. The molecular structures and stackings were presented and the effects of solvent, counteranions and metal ions on the molecular packing arrangement of the complexes were analyzed.

Reversible vapochromic behavior of a porous copper(II) coordinator polymer constructed from a flexible hinglelike ligand is investigated by adsorption measurements. The isotherms show large hysteretic and stepwise profiles, suggesting the occurrence of the guest-induced framework transformation.

A new three-dimensional (3-D) jungle-gym-like open metal-organic framework is synthesized from a two-dimensional (2D) layer compound using a heterogeneous pillar insertion reaction. Both the starting 2-D layer and the resulting 3-D open compounds are characterized using X-ray crystallography.

Research has been conducted on the metal-organic coordination polymers. The preparation and the crystal structure of the 3D coordination networks assembled by AgNO (sub)3 oxalate and ppa and bpp ligands are discussed.

Counteranions play a key role in both obtaining large crystals suitable for X-ray analysis and in regulating the coordination of solvent molecules to the metal ions. Research focusing on copper(I) coordination polymers with the tridentate ligand 2-pyrazinecarboxyamide has established that it is possible to use this basic molecular building block to produce unusual hexanuclear circular arrays of ligand-bridged Cu(I) ions. Assembled helical structures of copper(I) complexes with tridentate oligopyrazine ligands can be produced by introducing an appropriate spacer group between the metal-binding sites.

The reaction of [beta]-amino-[beta]-(pyrid-4-yl)acrylonitrile with the aromatic dicarboxaldehydes 9,10-bis(4-formylphenyl)anthracene and terephthalaldehyde has produced the dihydropyridyl products, where the material has incorporated pyridyl-decorated channels and has shown permanent porosity in the solid state. Thermal removal of solvents from the solvates has resulted in conversion to denser phase, which has shown no effective permanent porosity.

Systematic functionalization of porous coordination polymers (PCPs), [[[Cu.sub.2][(L).sub.2](ted)].sub.n] (L = dicarboxylates and ted = triethylenediamine), by introducing various substituents onto the component organic ligand (L) is performed to regulate the radical polymerization of methyl methacrylate (MMA) in the nanochannels. Accurate molecular dynamics calculations are used for determining structures of [[[Cu.sub.2][(L).sub.2](ted)].sub.n] and have disclosed that the specific channel shape of [[[Cu.sub.2][(2,5-dimethoxyterephthalate).sub.2](ted)].sub.n] has induced the large tacticity change of the resulting poly(methyl methacrylate) (PMMA).

A 3-dimensional (3D) pillared-layer coordination polymer is prepared that has shown a rotatable pillar acting as molecular gate, framework flexibility with slippage of the layers and coordinatively unsaturated metal centers as guest accessible sites through the removal of the water coligands. A molecular gate is reported that has a rotational module displaying a locking/unlocking system that has accounted for gate-opening type sorption profiles.