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Research has been conducted on the transition metal half-sandwich complexes with 1,1-dichalcogenolate ligands. The preparation of these complexes via the reactions of Cp*MCl (sub)4, where Cp*= eta (super)5 -C (sub)5 Me (sub)5 and M= Mo, W, with the potassium salt or the analogous seleno compound is described.

Research has been conducted on the homologous tungsten(VI) derivatives. The reactivity, epoxidation mechanism and applicability of these compounds have been investigated and compared to those of the molybdenum(VI) compounds and the details are presented.

Research has been conducted on the reductive metal cluster growth on nanowires. Results indicate that the reduced metal clusters grow to different sizes in the nanometer regime on the SiNW surfaces.

Research has been conducted on the di- and tricobalt Dawson sandwich complexes. The synthesis of these complexes has been carried out by the reaction condition modification and the characterization of the complexes has been carried via (super)31 P NMR spectroscopy, elemental analysis and IR.

Research has been conducted on the (fulvalene)W (sub)2 (H) (sub)2 (CO) (sub)6 reaction with 2/8S (sub)8 in tetrahydrofuran. The quantitative formation of (fulvalene)W (sub)2 (SH) (sub)2 (CO) (sub)6 and the crystal structure of the complex are reported.

Research has been conducted on the carbonates and trichlorobenzoate. The metal-catalyzed allylic substitution reaction of these compounds has been investigated and the metal complexes which contain iridium, palladium, tungsten, rhodium and molybdenum have been compared as catalysts.

Research has been conducted on the lacunary polyoxoanion alpha-P (sub)2 W (sub)15 O (sub)56 (super)12-. The purity of this compound has been determined via the conversion of alpha-P (sub)2 W (sub)15 O (sub)56 (super)12- into tri-Nb (super)5+ - and V (super)5+ -containing polyoxoanion and the details are reported.

Research has been conducted on the polyoxometals which contain Keggin and Wells-Dawson moieties. The study of the Fe(III) (sub)3 capped Wells-Dawson complex has been carried out and the stability of the polyoxometals based on the trivacant Wells-Dawson units, pH and incorporated metal's intrinsic Jahn-Teller distortion has been investigated and is discussed.

Research has been conducted on the intermetallic electron transfer. The effect of this electron transfer on the magnetic coupling mode has been investigated in the face-shared bimetallic complexes via the use of the density functional theory and the details are reported.

Research has been conducted on the fullerene-like nanoparticles. The nanoparticles have been intercalated via the alkali metal vapor exposure by the two-zone transport method and the details are reported.

Research has been conducted on the oxo transfer reactions. The mechanistic investigation of the oxo transfer mediated by the biological metal is presented.

Research has been conducted on 4-pentyl-1-ol endo- and exo-cycloisomerizations. The study of these cycloisomerizations carried out computationally via the use of density functional theory both in the presence and in the absence of tungsten carbonyl catalyst is presented.

Research has been conducted on the metal-metal multiply bonded complexes. The third-order nonlinear optical responses of complexes' solutions have been measured via the picosecond degenerate four-wave mixing and the details are reported.

Research has been conducted on the [Co (super)II W (sub)12 O (sub)40] (super)6- excited configurations. The calculations of the configurations' multiple splittings carried out via the use of the density functional theory are presented.

Research has been conducted on the niobium, tantalum, molybdenum and tungsten isopolyanions. The structure and bonding of these isopolyanions have been investigated via the use of density functional methods and the details are presented.

Research has been conducted on the tetrathiometalates. The synthesis of the five-coordinated trithiotungsten complexes with the dmsp and dpsp ligands has been carried out and the results demonstrate that the phosphine coordination increases trithio(thiolato) structures in solution.

Research has been conducted on the polypyridyl d (super)6-W(0) and Re(I) carbonyl complexes. The results of the photophysical and photochemical analysis of some of these complexes which incorporate ferrocene end-capped pyridine ligands are reported.

Research has been conducted on the heteroatomic closo-[1-M(CO) (sub)3 (nu (super)4 -E (sub)9)] (super)4- (E= Sn, Pb; M= Mo, W) anions. The crystal structures of these anions and solution characterization of the [1-M(CO) (sub)3 (nu (super)4 -Sn (sub)9)] (super)4- (M= Cr, Mo, W) anions have been investigated and the results of the NMR spectroscopy analysis of the anions are presented.

Research has been conducted on the alpha- and beta-Keggin heteropolytungstates of the second-row main-group heteroatoms. The thermodynamic and kinetic stabilities of these compounds have been investigated, and the preparation of their isomerically pure derivatives is described.

Research has been conducted on the mercury-containing purple corner-shared [Mo (sub)6 HgS (sub)8 (H (sub)2 O) (sub)18] (super)8+ double cube derivative of green [Mo (sub)3 S (sub)4 (H (sub)2 O) (sub)9] (super)4+. The preparation of this derivative under the air-free conditions via the reaction with Hg (super)0 and with Hg (super)I (sub)2 is described.

Research has been conducted on the diferric sandwich-type polyoxometalate. The reaction of this compound with the excess aqueous Cu(II) and Co(II) which produces a d-electron-metal substituted polyoxometalate is described.

Research has been conducted on the propargyltungsten compounds with the tethered epoxide. The preparation of these compounds from the available materials has been carried out in the presence of the different Lewis acids and the results indicate that most of the compounds promote the [3+3] epoxide cycloaddition with its tethered propargyltungsten group.

Research has been conducted on the cubane-type clusters. The preparation of these clusters via the reaction of the incomplete cuboidal trimers with CuCl or CuBr or the mononuclear copper complex in tetrahydrofuran has been carried out and reported.

Research has been conducted on the Group 14 germanium. The incorporation of this Group into the incomplete cuboidal clusters [M (sub)3 E (sub)4 (H (sub)2 O) (sub)9] (super)4+ (M=Mo, W; E=S, Se) has been investigated and the results are reported.

Research has been conducted on the coordinated phenoxide groups in [W(ethanediolate dianion) (sub)2 (OC (sub)6 H (sub)3 Me (sub)2 -2,6] and [W(ethanediolate dianion) (sub)2 OC (sub)6 H (sub)3 (super)i Pr (sub)2 -2,6). The chloride-for-alkoxide substitution and the preparation of the complexes of the [WCl (sub)2 (ethanediolate dianion)(OAr) (sub)2]-type have been investigated and discussed.

Research has been conducted on the triply-bonded ditungsten complexes. The mechanisms of the cis-trans isomerization in these complexes with stoichiometry W (sub)2 Cl (sub)4 (NHEt) (sub)2 (PMe (sub)3) (sub)2 have been investigated via the static density functional calculations and Car-Parrinello simulations and the results are reported.

Research has been conducted on the quaternary antimonides which contain transition metals. The preparation of these compounds has been performed via the reaction of the elements and the results indicate that these antimonides are isostructural and crystallize as the W (sub)5 Si (sub)3 -type structure substitutional variants.

Research has been conducted on the tosylate cluster. The preparation and characterization of the cluster have been performed via the use of IR and NMR spectroscopy, elemental analysis and X-ray crystal structure study and the results indicate that this cluster is a useful material for the pseudohalide cluster preparation.

Research has been conducted on the coordinatively unsaturated W(IV)-bis(pyridine) compounds. The synthesis of these compounds has been carried out via arene displacement and the results indicate that these compounds are more reactive source of W(IV) than the arene complexes.

Research has been conducted on the halogen-transfer agent tungsten hexachloride which produces tungsten oxo fragment and salicoyl chloride via the reaction with the salicylic acid. The origin of the ubiquitous oxo ligands and the reaction pathways generating these oxo products have been investigated and the results are reported.

Research has been conducted on the metal-oxygen cluster species, polyoxometalates. The structure and properties of these polyoxometalates have been investigated and the results are reported.

Research has been conducted on the oxothio- and bis(thio)tungsten(VI) complexes. The synthesis of these complexes has been carried out and the results of the spectroscopic, structural and electrochemical analysis of the compounds are presented.

Research has been conducted on the structurally characterized tungstoenzymes containing mononuclear active sites. The stable coordination units of bis(dithiolene)tungsten (IV,V,VI) complexes related to the enzyme sites have been examines via the exploratory synthesis and the results indicate that tungsten(IV) complexes which have been obtained via substitution are carbonyl displacement products.

Research has been conducted on the tungsten-oxygen-chlorine clusters. The results of the reaction in which the entrance to the tungsten oxochloride cluster chemistry is provided via WOCl (sub)4 reduced with bismuth metal are reported.

Research has been conducted on the large polyoxotungstates. The synthesis of these compounds has been carried out via the lanthanide cation reaction with the As (sub)4 W (sub)40 anion and the results are presented.

The study examines coordination modes and substitution kinetics of two tungsten (0) thiouracil derivatives. Evaluation of coordination modes and CO ligand reactivity has been done by HF and DFT theoretical methods.

Pyrococcus (P.) furiosus relies exclusively on tungsten in forming its three different catalytically active tungsten-containing enzymes. Results revealed that P. furiosus cultured in molybdenum- or vanadium-rich media exhibited no significant differences with bacteria grown in tungsten-containing media. In addition, bacteria grown in molybdenum or vanadium did not express active isoenzymes containing these trace elements.

Research has been conducted on the tungsten trithio and tetrathio complexes. The alkylation reactions of these complexes with 2,6-bis(bromomethyl)pyridine have been carried out and the details are reported.

Research has been conducted on the photoinduced DNA cleavage. Results indicate that this cleavage occurs upon the photolysis of such complexes as CpM(CO) (sub)n R, where M= W and Fe and R= CH (sub)3, C (sub)6 H (sub)5 but not when M= Cr or Mo.

Research has been conducted on benzyl chlorides. The oxidation of these compounds directly to benzoic acids has been carried out via the eco-safer way using 30% hydrogen peroxide with Na (sub)2 WO (sub)4 .2H (sub)2 O as a catalyst and [CH (sub)3 (n-C (sub)8 H (sub)17) (sub)3 N] (super)+ HSO (sub)4 (super)- as a phase transfer agent without organic solvents.

The metal requirements of Methanococcus maripaludis for nitrogen fixation were analyzed in a nitrogen-free medium lacking molybdenum to determine the role of molybdenum in the conversion of atmospheric N2 to ammonia. The addition of molybdenum in nitrogen-free medium containing Methanococcus maripaludis induced growth under nitrogen-fixing conditions in the absence of vanadium and tungsten. However, diazotrophic growth was inhibited by the addition of tungsten and molybdenum. The effects of molybdenum of growth also indicated the presence of molybdenum-type nitrogenases.

Research has been conducted on the functionalization of hexamolybdates with aromatic amines under mild conditions. Results indicate that this reaction can be extended to the [MoW (sub)5 O (sub)19] (super)2- mixed-metal cluster and can allow the synthesis of the arylimido derivatives of this cluster.

Research has been conducted on the [WO (sub)2 F (sub)4] (super)2- anion. The coordination to the charged sites on this anion in the new compound using the additional hydrogen bond from the hydroxyl group distinguishes the oxide and fluoride ligands and the results indicate that the new compound provides the insight into the oxide fluoride anion group and the origins of their solid-state structures.