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The synthesis and structures of ([Et.sub.3]NH)[In[(SeC{O}Ph)].sub.4].[H.sub.2]O and one dimensional coordination polymeric compounds A[(MeCN).sub.x]M[(SeC{O}Ph).sub.4]] (A = Na, K; M = In, Ga; x = 0, 2) is explored the chemistry of metal thio- and selenocarboxylates. The findings show that [[M[(SeC{O}Ph)4].sup.-] could be used as metalloligand to bind to alkali metal ions and [[In[(SeC{O}Ph]4].sup.-] could be used for Cu(I) and Ag(I).

The syntheses and structures of the compounds [M{[In(SC{O}Ph)].sub.4)]}.sub.2] (M = Mg and Ca) are presented. It is shown that the [[M{[In(SC{O}Ph)].sub.4)]}sup.-] ligand can be used as metalloligand to bind to [Mg.sup.II] and [Ca.sup.II] ions and isolated [M{[In(SC{O}Ph)].sub.4)]}.sub.2] and Ca[(H2O).sub.x]{In[(SC{O}Ph}.sub.4]}.sub.2]].yH2O, which are molecular compounds unlike the alkali-metal derivative of[[M{[In(SC{O}Ph)].sub.4)]}sup.-]

The direct deposition of crystalline molybdenum sulfide (MoS2) is reported using a single-source precursor based on tetrakis(diethylaminodithiocarbomoto)molybdate(IV). The chemistry of the precursor adsorbed on a range of substrates is studied using in situ X-ray photoelectron spectroscopy.

Research has been conducted on electroactive multimetallic compounds with Pt (sub)2 (mu-S) (sub)2 M] core (M= Hg, Au). The synthesis of these compounds carried out via the use of electrospray mass spectrometry is described.

Research has been conducted on the one-dimensional coordination polymers. The synthesis and structures of these polymers and the ability of [M(SC{O}Ph) (sub)4] (super)- anion to behave like anionic metalloligand have been investigated and discussed.

Research has been conducted on the metal exchange reaction. The methodology in monitoring this molecular transformation which converts a one active site complex into the two active site complex has been developed and is described.

Research has been conducted on the model complexes for the intermediate species in the biological transmission and racemization of the amino acids with the pyridoxal phosphate. The isolation of the single-stranded metal-coordinated polymers from the reaction mixture of Cu(ClO (sub)4) (sub)2, N-(2-hydroxybenzyl)-beta-alanine and 1,10-phenanthroline has been carried out on the hydrogen- and covalent-bonding basis in a solid state and the results are discussed.

The compounds (Me(sub 4)N)[A{M(SC{O}Ph)-(sub 3}(sub 2] were synthesized by reacting appropriate metal chloride and the structures were determined by single-crystal X-ray defraction method. Solution metal NMR studies showed the concentration-dependent dissociation of the alkali metal ions in the trinuclear anions.

The Au(I) complexes (AuL2)+, (LAuCl) and (AuCl2)-, where L is 2-aminopyridine, can be formed from the reaction of L with (Au(SMe2)Cl). These complexes co-crystallize to form the trinuclear Au(I) unit ((AuL2)+(LAuCl)(AuCl2)-). An X-ray analysis of this trinuclear gold compound revealed that (AuL2)+, (LAuCl) and (AuCl2)- are arranged in a pattern [+ neutral -] and that these complexes assemble into 2D networks through extensive aurophilic and N-H***Cl hydrogen bonding interactions.

The first known metallacycles known have been synthesized through the oxidative addition of tin-sulfur, tin-selenium, tin-tellurium and germanium-tellurium bonds to platinum(II). The syntheses were carried out under a nitrogen atmosphere using standard Schlenk procedures. Their physical properties were then studied through 1H, 119Sn and 195Pt nuclear magnetic resonance spectroscopy. These complexes have catalytic properties and undergo unique distribution reactions. The order of reactivity of the group 14-group 16 bonds is Sn-Te, Ge-Te >> Sn-Se > Sn-S although the Ge-Se and Ge-S bonds were inert.

The anion (Cd(S(O)CPh)3)- exhibits polytopal isomerism around the CdS3 skeleton which exhibit both planar and pyramidal geometries in the rhombohedral form of the anion. The structural characterizations of the anion and its monoclinic as well as rhombohedral modifications are presented. Planar-pyramidal isomerism among three-coordinate species is a very rare occurrence.

The synthesis and characterization of an extended range of salicylaldehyde acyldihydrazone ligands and their dicopper(II) complexes formed from both neutral or basic and dilute acid solutions are presented. Prepared compounds have been characterized by a range of physicochemical and spectroscopic techniques and proton and metal ion stability constant data have been determined.

The chloride inclusion anionic complexes ((bowl)Cu4(mu-Cl)4-(mu3-Cl))- (2a) and ((bowl)Ag4(mu-Cl)4(mu4-Cl))- (2b), where bowl is (PhCH2CH2CHC6H2O2PPh)4, exhibit selective binding with metal cations. The metal cation inclusion results from chelation of the four mu-Cl groups in the complex. The cesium complex of (2a.Cs)2 (3d) and mercury complex of 2b.Hg (5a) have sandwiched metal ions present between the corresponding anionic complex. The metal cation complexation affects the binding of the occluded chloride anion in 3d.

Reaction of Zn(NO3)2.6H2O, Cd(NO3)2.4H2O or HgCl2 with Et3NH+PhCOS- and (Ph4E)X (E = P, X = Br; E = As, X = Cl), when mixed proportionately in the presence of aqueous alcohol, produces salts of (Ph4E)(M(SOCPh)3)- (M = Zn, Cd, Hg). The products (Ph4P)(Zn(SOCPh)3), (Ph4As)(Cd(SOCPh)3) and (Ph4P)(Hg(SOCPh)3) are analyzed for structure determination. The metal atoms attached to three sulphur atoms have a trigonal planar geometry in the anions. Compared to the MS3 kernels of thiolates, the metal NMR signals of thiobenzoates have a greater shielding.

The oxo cluster (Ru3{mu-3-O}{mu-3-CO}{CO}3{mu-dppm3) prepared from oxidation of (Ru3{CO}6{mu-dppm}3) (dppm = Ph2PCH2PPh2) with silver and O2, suffer reversible protonation to yield the respective hydroxo cluster (Ru3{mu-3-OH}{mu-3-CO}{CO}3{mu-dppm3)+. A fluxionality and steric hindrance are observed in the clusters, based on the M3(mu-dppm)3 unit.

Synthesis of phosphonito-cavitand and phosphinito-calixresorcinarene involves the incorporation of four and eight phosphinite units, respectively, into a bowl-shaped calixresorcinarene. Transition metals are incorporated on the upper rings of the calixresorcinarene bowl using these derivatives. X-ray studies of the chlorogold(I) complex of phosphonito-cavitand reveal that it has three AuCl units around the upper ring of the bowl and the fourth AuCl unit is folded inside the cavity.

A self-assembly reaction is used to produce adamantanoid complexes of Hg(II) with halides and thiolates in binding positions. The complexes are of the type (Hg4SR6X4)(super 2-) and various combinations of cat(super +)/R/X are produced. 199Hg NMR spectroscopy is used to analyze the dissociation effect at high temperatures. X-ray crystallography is to study the two adamantane-like complexes.

Studies of tripalladium-cluster isocyanide and diisocyanide complexes reveal that a 42-electron configuration is formed with triply-bridging isocyanides. The complexes differ from platinum analogs that possess 44-electron configurations with terminal isocyanides. The nickel complexes have a 48-electron configuration with triply-bridging isocyanides. The NMR spectra reveal broad resonances for the Ch2P2 and ligand methyl resonances.

NMR data validates the presence of ((mu-ER)6(CdPPh3)n(Cd)4-n)(super 2+) type cations and the (Ph3PCd((mu-ER)CdPPh3)3)(super 5+) open tetranuclear Cd(PPh3)2(ClO4)2:Cd(ER)2:PPh3 systems. Adamantine-like phosphine complexes are identified, and x-ray techniques study the crystal and molecular structure of ((mu-SPri)6(CdPPh3)2(CdOClO3)2).EtOH. ((mu-ER)6(CdX)sub 4)(super 2-) complexes are stable at room temperatures.

Ruthnium acetate is reduced with NaBH4 in the presence if Ph2PCH2PPh2 (dppm) and CO to form (Ru2(mu-CO)(CO)4(mu-dppm)2). The reaction, which also produces low yield of Ru3(CO)(6(mu-dppm)3), is followed by protonation to form Ru3(mu-H)(CO)6(mu-dppm)+. X-ray diffraction analyses show the structural differences in the configuration od the original product andits proton adduct. The results also show the fluxionality of the cluster cation with hydrogen migration occurring between edges and sides of the Ru3 triangle.

The salt (Me4N)(Na(Cd(SOCPh)3)2) was synthesized by the reaction of Cd(NO3)2.4H2O, NaSOCPh and Me4NCl in aqueous methanol. The salt displayed solubility in THF, Me2CO, MeCN, DMSO and DMF and crystallize by the addition of MeCN. Characterization by single-crystal X-ray crystallography showed that the trinuclear anion consists of six thiobenzoate ligands, two Cd(II) centers and a Na(I) center. Metal NMR spectra of the salt in Me2CO and MeCN were also carried out.

The protonation of CoRh(CO)3(mu-dppm)2 (dppm = diphenylphosphinomethane) leads to shortening of the Co-Rh bond. The phenomenon is unique among bimetal complexes, where the expected effect is bond lengthening due to conversion from a 2c-2e to a 2e-2c bond. Spectroscopic studies show that the Co-C-O bond angle decreases on protonation, giving more symmetry to the carbonyl bridge. This symmetry and the fact that the unprotonated form has a 16e-18e instead of a 2c-2e metal-to-metal configuration may account for the rare bond shortening. Additionally, the noted fluxionality of the mu-H complex in solution is traced to inversion of the CoRh(mu-H) unit.

The stereochemistry of the first homoleptic transition metal thiobenzoate complexes, (Ph4P)(M(SC(O)Ph)3) (M = Mn, Co, and Ni), was investigated. Results showed that the anions of the complexes have the lambda-form, which was confirmed by refining their Flack parameters. Furthermore, the bulk compounds did not exhibit any optical activity in CH2Cl2 solution. Based on these findings, it may be concluded that the bulk compositions are in agreement with the determined structures and that the bulk consists of anions with the fac geometry only.

The self-assembly of trans,trans-muconic acid ([H.sub.2]muco), a longer spacer ligand, 4,4'-bis(pyridyl)ethylene (bpe), cobalt(II) ions is described by slow diffusion method. The formation of a particular isomer in major quantity is obtained by varying the countercation of the muconate salt in different solvents, by layering and by changing the order of the components.

The synthesis, structural characterization and magnetism of a [[L.sub.2][Ni.sub.2]Ln][Cl[O.sub.4] family of compounds is reported. The new compounds with mixed metal 3d/4f single-molecule magnet were obtained by the reaction of L[H.sub.3] with Ni[(Cl[O.sub.2]).sub.2].6[H.sub.2]O and lanthanide salts in a 2:2:1 ratio in the presence of triethylamine.

A facile synthesis of a new linear trinuclear [Co.sub.2]Gd complex is presented. It shows that a linear trinuclear mixed-metal [Co.sub.2]Gd complex supported by two phosphorus-based multisite coordination ligands shows a single molecule magnet.

The synthetic routes are developed for a wide variety of thermally stable metal thiocarboxylates and selenocarboxylates. The potential use of some of these compounds as single-source precursors for making metal sulfide and selenide bulk materials, thin films and nanoparticles are described.

A novel one-pot synthesis of close to monodispersed, one-dimensional (1D) AgInSe2 nanorods is reported, where the single-source precursor is thermally decomposed in mixed amine and thiol solution. The results have shown that perfect matching of two or more surfactants might be the key to obtaining high-quality nanocrystals for many novel materials.

A simple way to synthesize PbS nanocrystals with the ability to tune their morphology to spherical particles, dendrites, and nanorods at room temperature is described. The amines were used both as the catalyst and as the growth-control reagent, to demonstrate that the growth morphology of the nanocrystals could be controlled by using different amine or mixtures of capping groups.

The preparation of the phosphapalladacycle derived form 1-[(2,5-dimethyl)phenyl]ethyldiphenylphosphine in the optically active and racemic forms is discussed. The phosphapalladacycle methyl substituent was found to be axially located and the phosphapalladacycle was conformationally rigid in CDCl3.

Three novel methods for syntheses of altered oxa corroles having one free carbon in moderately good yields are presented. The reactions are maximized with various conditions by changing the meso substituents, acid catalyst concentration and properties of the solvent.

The reactivity of diethyl azodicarboxylate (DEAD)/diisopropyl azodicarboxylate (DIAD) with P(III) compounds bearing oxygen or nitrogen substituents is explored. The naive-looking reaction of DEAD/DIAD with P(III) compounds leads not just to the Morrison-Brunn-Huisgen (MBH) betaine, but has the potential to open up new frontiers.

Two highly air-sensitive asymmetric ligands plusmn-diphenyl[1-(1-naphthyl)ethyl]phosphine and its arsenic analogue [plusmn-L] are prepared and resolved by the fractionalization of a pair of diastereomeric palladium complexes including the appropriate ligand and ortho-metalated (R)-(1-(dimethylamino)ethyl)naphthylene.

Research has been conducted on cationic Cu(II) complex structures. The authors have investigated the effects of the reactants and water on the self-assembly of these structures.

Research has been conducted on [Cu (sub)3 (phis) (sub)3] (super)3+ cation structure. The authors report that the reaction of [Cu (sub)3 (phis) (sub)3](ClO (sub)4) (sub)3 with LiClO (sub)4 leads to rearrangement of the tricopper cationic structure in order to accomodate a Li (super)+ ion and to form [(ClO (sub)4)Li{Cu (sub)3 (phis) (sub)3}]-(ClO (sub)4) (sub)3.

Research has been conducted on chiral auziliary (+/-)-N,N-dimethyl-1-(2,5-di,ethylphenyl)ethylamine complex. The authors describe the design and synthesis of the complex carried out from 1-acetyl-2,5-dimethylbenzene.