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The experimental results on transition metal doping of ZnO is reviewed and the material that can be made with a single phase at high levels of Co incorporation is shown. Solutions involve either cubic phase ZnO or the use of additional stressor layers to create a larger spin splitting in order to get a polarized light emission.

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).

The effect of a finite thickness transition layer on the character of charge particle localization at the boundary separating domains with different electric permittivities is studied. It is shown that the effective potential at the location of the particle can be determined using perturbation theory and the conditions for the validity of the theory are discussed.

Several ab initio density functional calculations are carried out to explain the structure, energetics and magnetic properties exhibited by the transition metal doped [Zn.sub.12][O.sub.12] clusters. The defects formed in the cluster are shown to be extremely beneficial for the stabilization of the compound.

The phenomenological band coupling model is employed to explain the origin of magnetism, as observed in the transition metal doped CuI systems. The electronic structures of the doped CuI compound are also discussed.

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.

A density-functional theory is used for studying the electronic structure of pure and 3d transition metal (TM) (Sc, Ti, Cr, Mn and Ni) incorporated [alpha]-[Fe.sub.2][O.sub.3]. The importance of results is discussed in terms of the utilization of hematite as a visible-light photocatalyst.

Photoelectrochemical [H.sub.2] production by solar irradiation has determined the carrier transport properties, reactivity, light absorption strength and has impacted the materialEs efficiency as a photoconverter. The localization or delocalization of the band edges are achieved either due to the orbital nature of the bands or the structural morphology of the material.

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.

The effect of in-plane lattice strain on the atomic and electronic properties of low-index transition metal (M = Ti, Nb and Ta) carbide surfaces is analyzed by first-principles molecular dynamics calculations by using a pseudopotential plane-wave technique. The surface energy calculations have shown that surface stability is governed by the applied strain.

The preparation of a family of wide-band-gap ternary oxide ferromagnetic semiconductor films with high transition metal concentration is presented. The wide gap oxide ferromagnetic semiconductors with controllable spin-polarized electrical transport could find significant application in spintronics devices as a spin injection source.

The thermoelectric properties were examined for a series of Fe, Mn, and Cu doped [Ca.sub. 3][Co.sub.4][O.sub.9]+[delta] samples, [Ca.sub.3][Co.sub.4][O.sub.9+[delta] (M = Fe, Mn, and Cu), fabricated by cold high-pressure compacting technique. Fe doped samples of [Ca.sub.3][Co.sub.4][O.sub.9+[delta] with highest ZT values could find use as a promising candidate for thermoelectric applications at elevated temperatures.

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.

The density of states and optical properties of many transition metal compounds are simulated by using local density approximations+U. The results have shown that s electrons of nontransition elements in the compounds does not have the same contribution on the number of valence electrons and the parameter in the Levine model is improved, leading to better prediction for dielectric constants of transition metal compounds.

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.

An empirical equation is used for achieving the scaling of nonlinear two-photon absorption to optical bandgap in transition metal glasses. The relationship between the nonlinear absorption coefficient and the bandgap energy by using Tauc's parabolic band model is discussed in terms of electronic structure of constituent oxides, ionic polarizability, hyperpolarizability of cations, nonbridging oxygen bonds and the cationic bond-length approach.

Several high-pressure x-ray diffraction studies are conducted to determine the various properties of the group IV transition metals-based bulk metallic glasses under high pressure. An increase in the pressure of the system is shown to lead to excess free-volume, which in turn is shown to cause an increase in the density of the system.

The Monte Carlo method in the canonical ensemble is used for studying magnetization reversal in multilayers of amorphous transition metal and rare earth elements. The results have shown that the atom probe tomography profile has favored perpendicular magnetic anisotropy, which has agreed with magnetic measurements.

Near normal infrared reflectivity spectra of ~550 nm thick films made of cosputtered transition metal nanograins and Si[O.sub.2] in a wide range of metal fractions are reported. A remarkable resonance observed at the angle dependent oblique reflectivity of globally insulating [Co.sub/0.38][(Si[O.sub.2]).sub.0.62], [Fe.sub.0.34][(Si[O.sub.2]).sub.0.66], and [Ni.sub.0.28][(Si[O.sub.2])].sub.0.72] due to the excitation by normal to the film electric fields of defect localized electrons in the metallic nanoparticles are also reported.

The spectroscopic methods were used to study the electronic structure and optical properties of conducting ternary transition metal nitrides consisting of metals of different groups of the periodic table of elements. The results provide insight into the plasma energy of the fully dense [Ti.sub.x][Ta.sub.1-x]N varying between 7.8 and 9.45 eV and the optical absorption bands manifested due to the N p -> Ti/Ta d interband transition.

A study was conducted to explore the influences of N vacancies on the transition metal (Cr, Mn, Fe, Co, Ni, and Cu) doped GaN at the levels of the local spin density approximation (LSDA) and LSDA+U (Coulomb interaction). The findings for the magnetic moments of doped GaN with N vacancies which are insensitive to the distances between N vacancies and the doped transition metal ions could be used to elucidate the effects of N vacancies on the magnetic properties of the transition metal doped GaN.

First-principles method is used to assess the structural, mechanical, and electronic properties of 5d transition metal diborides M[B.sub.2] (M=Re, W, Os, Ru). The high modulus, large strength, and high hardness exhibited by the 5d transition metal diborides is attributed to the presence of strong directional covalent B-B and M-B bonds in the electronic structures of the materials.

The magnetic properties of transitionlike metals are discussed within the single-site approximation and the metal is described by two hybridized bands one of which includes Coulomb correlation. The results have shown that ferromagnetism occurs for adequate values of hybridization, correlation and occupation number.

Deep level transient spectroscopy is used for examining the electronic properties of the 3d transition metal impurities titanium and chromium in crystalline germanium. The studies have shown that Ti in germanium is a double acceptor, while Cr is a triple acceptor with a donor level close to the valence band.

Molecular dynamics simulation is used for examining the interface and surface structure of transition metal (TM) (Fe, Co, Ni) thin film deposited on Al(001) substrate at atomic level. The different structural and intermixing characteristics at the interface are described in terms of lattice matching, cohesive energy and local acceleration effect.

First-principles methods are used for studying the mechanism of defect formation and electronic structures for 3d transition-metal impurities doped in silicon nanowires. The results have shown that the defect formation energies of Mn and Fe impurities are lower than those of V, Cr, and Co impurities in silicon nanowires.