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The well-known photoreduction of polyoxometalates by alcohols are exploited to produce the reduced species, which cannot be directly produced electrochemically in nonaqueous solvents. Photochemistry is a reliable means to produce stable reduced transition metal substituted heteropoly tungstates in nonpolar media, where they hold promise as multielectron reduction catalysts.

Single-crystal structure determinations of nine transition metal hexafluorides are presented. All compounds crystallize alike and have the same molecular structure and within the limits of precision, no systematic deviation from octahedral symmetry can be established.

Electronic structure control of the nucleophilicity of transition metal-thiolate complexes is studied. The combined results suggest that Ni(II) may serve as a competent replacement for Zn(II) in alkyl group transfer enzymes, turnover may be limited by slow product release from the Ni(II) center.

Periodic ab initio QM calculations are employed in order to study structure and redox properties of Cr, Mn, Fe, and Co trivalent transition metal dopants in A1POs-34. The results show that the local environment of Mn and Co dopants is a distorted tetrahedron due to the Jahn-Teller distortions.

The formation of DMSO (dimethyl sulfoxide) complexes for a number of triply charged ions of the metals, including both transition metals (V, Cr, Fe) and those of the main group (A1, Ga, In, Bi) is reported. Fragmentation of M(super 3+) (DMSO)(sub n) for these metals (plus La, Yb, and Sc) is characterized in detail using collision-induced dissociation (CID).

A series of poly(N-heterocyclic carbene) complexes in which the carbene functionalities are orthogonally connected to the main chains of the respective polymers are prepared by oxidative electropolymerization of various bis(bithiophene)-substituted monomers with appended transition metal or main group entities (M = Ir, Au, Ag, S). Electrochemical analyses of the polymer thin films have shown that they have displayed highly reversible electrochromic phenomena.

The synthesis and electrochemical properties of highly ordered mesoporous T-[Nb.sub.2][O.sub.5], L-[Ta.sub.2][O.sub.5], and TaNb[O.sub.5] solid solution thin film with iso-oriented layered nanocrystalline domains are described. The studies have shown that the group V transition metal oxides can be produced with a high degree of crystallographic alignment on virtually any substrate in contrast to classical solution-phase epitaxy that needs the use of a single-crystalline substrate to achieve oriented crystal growth.

A general synthetic method is developed for preparing high-quality, (100)-terminated [Pt.sub.3]M nanocubes (M = Pt or 3d-transition metals Co, Fe and Ni). The resultant monodisperse nanocubes, in which Pt is partially substituted, have displayed unusual electrocatalytic characteristics, which have given an alternative for developing high-performance electrocatalysts for use in fuel cells.

Periodic, self-consistent density functional theories (DFT-GGA) are used to study the structure sensitivity of methanol electrooxidation on eight transition metals (Au, Ag, Cu, Pt, Pd, Ir, Rh, and Ni). The methanol electrooxidation trends on various metal surfaces are described by the free energies of adsorbed CO* and OH*.

Density functional theory (DFT) is used for examining 132 binary-alloyed nanoparticle systems and their segregation energies are explored to determine core-shell preferences. A universal description is provided for core-shell preference via tight-binding theory that has reproduced the DFT segregation energies and has confirmed the electronic origins and correlations for core-shell behavior.

A new [Cd.sup.2+]-selective ratiometric fluorescent sensor (CadMQ) is described. This probe has displayed excellent [Cd.sup.2+]-selectivity over transition metal ions in aqueous media and it is shown that CadMQ is a useful tool for detecting changes in [Cd.sup.2+] concentrations in living mammalian cells.

The energetics, as well as the electronic structures of the chelate systems consisting of the transition metal (TM) ions and a peptide nanoring, is discussed. The electrostatic interaction is shown to lead to the trapping of the TM cation by the used cyclic peptide skeleton.

The article discusses the design and preparation of new MO6-class density functionals that are widely used in computational chemistry. These functionals are found to be depended on the spin densities and spin density gradients and are found to be extremely effective and cheap.

A comparison of the electronic, magnetic, and structural properties of a series of five-coordinate first-row transition metal ions ([M.sup.2+] where M = Mn, Fe, Co, Ni, Cu, Zn) ligated by a tripodal thiolate-containing ligand [[(tren)-[N.sub.4][S.sup.Me2]].sup.1-] (tren = tris(2-aminoethyl)amine) is reported. All of the metal complexes except Ni are isostructural and adopt a tetragonally distorted trigonal bipyramidal geometry favored by ligand constraints.

A phosphinate transition state analogue is incorporated within a triple-helical peptide template. The phosphinate triple-helical transition state analogue has high affinity and selectivity for the gelatinases and has represented a new class of protease inhibitors that have maximized the selectivity via interactions with both prime and nonprime active site subsites as well as with secondary binding sites.

A newly developed method to identify tert-Butyl nitrite (TBN) as an efficient NO equivalent for the activation of molecular oxygen, which could be applied to the oxidation of solid substrate of alcohols with high melting point and/or low solubility, is presented.

The solution properties such as complex stabilities, redox potentials, and some ligand field spectra of a series of first row transition metal complexes of various tetra-, penta-, and hexadentate bispidine ligands are reported. It is seen that the isomeric pentadentate ligands have very different stabilities with a variety of metal ions and depending on the metal ion, one of the isomers leads to more stable complexes than the hexadentate and the other to less stable complexes than the tetradentate ligand.

The experimental study is conducted to examine the silicon clusters mixed with a transitional metal atom generated by a double-laser vaporization method. Results show that the neutral cluster doped with a group 4 atom features an electronic and a geometric closing at n=16.

Several close homologues of [alpha]-amino-[beta]-carboxymuconate-[epsilon]-semialdehyde decarboxylase (ACMSD) were analyzed to study transition metal-catalyzed nonoxidative decarboxyaltion reactions. The enzyme homologues of ACMSD are involved in the catabolism of tryptophan and vanillate, the biodegradation of hydroxylbenzoates, and the thymidine salvage pathways in certain organisms.

The zero-point and temperature dependent vibrational corrections of the H-D spin-spin coupling constant [J.sub.HD] for six transition metal hydride and dihydrogen complexes are computed from a vibrational average of [J.sub.HD] as a function of temperature. A method is outlined by which the temperature dependence of the HD spin-spin coupling could be determined with standard quantum chemistry software.

The electrical resisitivity and x-ray diffraction measurements for the MMX-chain complex, [Pt.sub.2][(dtp).sub.4)]I were performed under high pressure. The suppression of the metal-insulator transition to 70 K, the lowest known for any one-dimensional purely d-electronic conductors based on transition-metal complexes at 2.2 GPa is observed.

The synthesis of aryl radical anion sigma-bound to a transition metal is reported. The electron is proven to be localized in the naphthyl unit, but reactivity is entirely different from that of the naphthide radical anion, as exemplified by water reduction to dihydrogen, rather than the expected ring protonation.

A series of transition metal coordination complexes designed to assemble on gold surfaces was synthesized, their electronic structure and transitions analyzed, and their magnetic properties studied. The assembled molecules exhibit properties similar to that of the bulk molecules, indicating little change in molecular structure outside of chemisorption.

The main electronic characteristics of methylidynes, methylidenes, and methyl-metals are described for the first-row early transition metals, together with alkali and alkali-earth compounds for comparison. Different methodologies like the atoms in molecules (AIF) and the electron localization function (ELF) are employed and compared with environmental data available.

A method for accelerated luminophore discovery through combinatorial synthesis is described. The photophysical properties of the resulting transition-metal-based chromophores were compared against a series of analogues, traditionally prepared species.

Aqueous M(super 3+)/M(super 2+) redox potentials for nine of the ten fourth-period transition metals, M, were calculated with the use of density-functional theory methodology in combination with the continuum solvation model. For the ions studied, the average absolute difference from experimental values is 0.29 V, with four out of nine potentials reproduced with better than 0.1 V accuracy.

The utility of electronegativity and the extended electronegativity function in describing the charge distribution in simple coordination compounds of both the representative and transition metal is explored. The absolute electronegativities and absolute hardnesses in conjunction with the extended electronegativity function show considerable promise in their application to coordination compounds.

The local crystal structure and electronic configuration of transition metal in x-ray amorphous MnO2 and CrO2 nanocrystals were examined by using X-ray absorption (XAS) spectroscopy at Mn K and Cr K-edges. The Mn K-edge XAS study reveals that tetravalent manganese was stabilized in alpha-MnO2-type local atomic arrangement consisting of the intergrowth of edge- and corner-shaped MnO6 octahedra.

The reactions of atomic Ni(super +), Cu(super +), and Zn(super +) with CS2 and COS are examined using guided-ion beam mass spectrometry. The ground phase ions of all the three metals are found to undergo endothermic reactions to form MS(super +) from both CS2 and COS, as well as MCS(super +) and MCO(super +) respectively.

The geometries and bonding energies were calculated at B3LYP/3-21G AND B3LYP/DZVP2 levels in a series of [M(eta6-C6H6)](Super n+) where M = Ti, V, Cr, Fe, Co, Ni, and Cu. A correlation between the total benzene charge and the frequency shift of the E1 ring vibration was evidenced that allowed interpretation of experimental data.

Fluorescence behavior of some structurally simple multicomponent systems has been studied in the presence and in absence of the transition metal salts. Preferential solvation of the fluorophore component of the multicomponent system by the water molecules of the hydrated salts of the metals has been identified as one possible origin of the unusually high fluorescence enhancement (FE) shown by some of the systems.

A mixed -phase electrocatalyst containing Pt metal and hydrous ruthenium oxides (RuO2H (sub y)) is found to be a more desired form of catalyst as compared to the Pt-Ru electro catalyzed oxidation of methanol. The active catalyst is discovered to be able to oxidize methanol fully to carbon dioxide and water.

The fundamental physics behind the scarcity of ferromagnetic ferroelectric coexistence is explored. It is found that, in general, the transition metal d electrons, which are essential for magnetism, reduce the tendency for off-center ferroelectric distortion.