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Optical spectra of Cu, Ag, and Au monomers and dimers at regular sites and oxygen vacancies of the MgO(001) surface were studied by time-dependent density functional study. The embedded cluster model was used which provided an accurate description of substrate relaxation and long-range electrostatic interaction.

A study was conducted to explore the photophysical properties of a series of luminescent copper(I) halide complexes with chelating ligand, 1,2-bis[diphenylphosphino]benzene (dppb) ([[Cu-([mu]-X)dppb].sub.2] and Cul(dppb)(P[Ph.sub.3])). The complexes in their excited state, both in solid state and in the solution, have showed favorable geometry of distorted tetrahedral and square-planar respectively.

A study was conducted to explore the photophysical properties of a series of luminescent copper(I) halide complexes with chelating ligand, 1,2-bis[diphenylphosphino]benzene (dppb) ([[Cu-([mu]-X)dppb].sub.2] and Cul(dppb)(P[Ph.sub.3])). The complexes in their excited state, both in solid state and in the solution, have showed favorable geometry of distorted tetrahedral and square-planar respectively.

The synthesis of some compounds belonging to the [Cu.sub.2]Sn[S.sub.3]-[Cu.sub.2]Si[S.sub.3] system and the crystal structure determination are described. The compounds were found to crystallize in a monoclinic structure like the pure phases and there was a smooth decrease in the crystallographic parameters with x despite the large difference between the radii of Sn and Si.

The characterization of CuO/Al2O3-ZrO2 catalysts by powder X-ray diffraction (XRD), electron spin resonance (ESR), temperature-programmed reduction (TPR), and temperature-programmed desorption (TPD) of CO2 and NH3 is reported. The dispersion of copper supported on Al2O3-ZrO2 is estimated as a function of copper loading and the changes in structure of the copper phase is identified with increased active-phase loading.

The photophysics of a series of bis-metal doubly N-confused hexaphyrins (1.1.1.1.1.1) was investigated using various fluorescent techniques and geometry-optimized ab inito calculations. Bis-Zn(II) and free-base doubly N-confused hexaphyrins show [pi]-[pi*] transitions around a hexaphyrin ring at the B3LYP/6-3IG level and the absorption spectra of bis-Cu(II) and bis-Co(II) doubly N-confused hexaphyrins are relatively broad due to large couplings between the metal d-orbitals and [pi]-electrons of the hexaphyrin rings.

Controlled microwave irradiation has been used to accelerate metal-catalyzed oxidation (MCO) reactions that site-specifically oxidize the amino acids bound to Cu in a metalloprotein. When combined with mass spectrometry, these MCO reactions provide a sensitive method for determining Cu-protein binding sites. In this work, we demonstrate that microwave irradiation can increase the rate of these site-specific oxidation reactions for Cu/Zn superoxide dismutase by at least 15-fold. By choosing the appropriate microwave power, changes to the protein's structure can be avoided while still accelerating the oxidation reactions. The maximum microwave power suitable for maintaining the protein's structural integrity can be readily determined by measuring the oxidation extent of different peptide fragments as a function of microwave power. Such determinations require several measurements and thus limit the overall throughput of this approach; however, these microwave-assisted reactions do provide good time resolution for studying dynamic changes to Cu-binding sites.

Solvothermal reactions of copper(I) cyanide with tetramethylammonium salts in anhydrous tetrahydrofuran (THF) lead to two novel halogeno(cyano)cuprates namely [Me4N][Cu3(CN)2Br2] with a 1 - D ribbon motif and [Me4N]2[Cu4(CN)5CI] and with a 3-D nanoporous framework. The optical and luminescent studies indicate that both the complexes are potential materials for semiconductors and long-lived highly luminescent material.c

The structural, emissive, and nonlinear optical properties of new CuI adducts with para-substituted trans-stibazolic and pyridinic ligands are reported. Single-crystal X-ray diffraction results indicate that the para-substituent on the organic ligand greatly influences the structural motif by its steric, electronic/steric, or bridging-donor properties.

The preparation, characterization, and photophysical properties of a series of Pt(super II)-M(super I) (M = Cu, Ag, Au) heterometallic complexes isolated by reactions of Pt(diimine)(edt) (edt = 1,2-ethanedithiolate) with M2(dppm)2(MeCN)(sub 2)(super 2+) (M = Cu, Ag, Au) are described. The study demonstrates that incorporating Pt(diimine)-(dithiolate) with [M2(dppm)2]2+ affords a feasible synthetic approach to attain heterometallic and multicomponent materials.

The adsorption behavior and crystallographic structure of copper phthalocyanine (CuPc) on highly oriented pyrolytic graphite (HOPG) at high substrate temperatures is described. Vibrational and structural results suggested that CuPc molecules formed a close-packed structure on the substrate with a face-to-face columnar growth that maintained the lying-flat orientation throughout the growth process.

The procedure applied for the L species on Pt/Al2O3 is used to prove that there is a linear relationship between the IR band of the L species absorbed on reduced 4.7%Cu/Al2O3 solid and its amount on the surface. The conclusion confirms that quantitative exploitations of the FTIR spectra recorded after adsorption of CO can be reasonably reformed at least under adsorption equilibrium.

The synthesis and structural characterization of 3d polymeric cluster [W(sub 4)S(sub 16)Cu(sub 16)Cl(sub 16)]n by the reaction of [NH(sub 4)](sub 2)[WS(sub 4)], CuCl, S(sub 8) and [NEt(sub 4)]Cl in the solid-state is presented. The result from the nonlinear optical (NLO) properties shows that the cluster exhibits large NLO absorptive and strong refractive behaviors

A study of the photoinduced DNA cleavage activity of the ternary tris(3-phenylpyrazolyl)borate copper(II) scorpionates [Cu(B){Tp(super Ph)}](ClO4) having heterocyclic bases B of 1,10-phenanthroline (phen), dipyridoquinoxaline (dpq), and dipyridophenazine (dppz) is carried out. The findings shows that the dpq and dppz complexes display efficient DNA cleavage activity due to the steric protection of the photosensitizer in the molecular bowl of [Cu{Tp(super Ph)}] moiety.

The oxygen plasma generated CuO(sub x) enhanced the hole injection into organic hole-transport layer (HTL). The analysis by X-ray diffraction pattern and Fourier transform infrared spectrum demonstrated that CuO(sub x) was a mixture of copper and copper oxides.

The significant covalent bonding character in the Au-C bonds in Au[(CN).sub.2.sup.-] is studied by using photoelectron spectroscopy and is compared with its lighter congeners (Ag[(CN).sub.2.sup.-] and Cu[(CN).sub.2.sup.-]). The covalent character in the Au-C bonding because of the strong relativistic effects is shown in Au[(CN).sub.2.sup.-], consistent with its high stability.

Highly enhanced nonlinear absorption cross section values of [Cu.sub.60](>DPAF-[C.sub.2M]), [C.sub.60](>DPAF-[C.sub.9]) and [C.sub.60](>DPAF-[C.sub.10]) dyads are detected in the 2.0 ps region in toluene. They are correlated to a trend showing higher efficiency in light transmittance attenuation for the dyads.

The near UV irradiation of aerated solutions of [([Et.sub.4]N).sub.2][Cu[Cl.sub.4]] in dichloromethane is used to understand the decomposition kinetics of C[H.sub.2][Cl.sub.2] by the buildup of HCl, [C.sub.2][H.sub.2][Cl.sub.4], and peroxides. The results showed that the hydroperoxide is formed through electron transfer from copper(II) to the peroxy radical followed by protonation of the resulting peroxide anion.

A combination of X-ray absorption (XAS) and pulsed electron paramagnetic resonance (EPR) spectroscopies were employed to examine the nature of distinct well-ordered type II site formed by riboflavin binding protein (RBP) which binds copper in a 1:1 molar ratio. The XAS and EPR spectroscopy showed evidence for role of a single histidine ligand in binding of RBP with copper in an [O.sub.3]N type II site.

The synthesis of a size series of copper indium selenide (Cu-In-Se) quantum dots (QDs) of various stoichiometries displaying photoluminescence (PL) from the red to the near-infrared (NIR) is described. The modular hot injection synthetic method has the potential to be extended to other QDs composed of I-III-VI semiconductors, which has allowed the exploration of the elemental compositions and electronic properties in QD materials.

The complexation of Cu(II) by amyloid-[beta] (A[beta]) is examined through the tandem use of fluorescence and electron paramagnetic resonance (EPR) spectroscopies. With the help of tyrosine fluorescence spectroscopy has provided mechanistic insights into the oxidation state of copper ions bound to A[beta], the binding heterogeneity and the impact of solution conditions on complex formation.

The article describes the synthesis, spectroscopic features, and thermal transformation chemistry of the first discrete Cu(II)-peroxynitrite complex. The results from the studies provide insight into the reactivity of the peroxynitrite complex involving O-O cleavage chemistry.

A high-temperature sealed-tube reactions and spark plasma sintering were used to prepare the single crystal and bulk powder samples of the quaternary lanthanum copper oxysulfides [La.sub.5][Cu.sub.6.33][O.sub.4][S.sub.7] and [La.sub.5][Cu.sub.6][O.sub.4][S.sub.7]. The detailed study results provided insights into crystal structures, optical properties and transport properties, and magnetic properties of both the complexes.

The reaction of Cu[(Sb[F.sub.6]).sub.2] with a stoichiometric amount to Xe[F.sub.2] in anhydrous hydrogen fluoride (aHF) at ambient temperature was used to prepare pure [Cu[(Xe[F.sub.2]).sub.2]][(Sb[F.sub.6]).sub.2]. The study provided insights into crystal structures, Raman spectra, and their comparisons with [Cu[(Xe[F.sub.2]).sub.6]][(Sb[F.sub.6]).sub.2].

The synthesis and characterization of two new copper complexes, [Cu(pbt)[Br.sub.2], [[Cu(pbt)[Br.sub.2](dmf)].sub.2] and a zinc complex, [Zn(pbt)[Cl.sub.2]], where pbt = 2-(2-pyridyl)benzthiazole) and dmf = dimethylformamide are reported. Both the pure ligand and [Cu(pbt)[Br.sub.2] were found to exhibit remarkable cytotoxic effects against selected cancer cell lines and [Cu(pbt)[Br.sub.2] in DMF cleaved with DNA oxidatively while the pure ligand pbt did not.

The microscopic origin of the in-plane ([G.sub.x1] [G.sub.y]) and out-of-plane ([G.sub.z]) Dzialoshinsky-Moriya (DM) exchange parameters are employed to study the [Cu.sub.3](II) clusters. The DM exchange 2[D.sub.DM] to zero-field splitting (ZFS) of the excited S=3/2 state is found to be significantly influenced by the tilt of the local magnetic orbitals.

The synthesis, crystal structures, and variable-temperature solid luminescence of copper(I) trimer, [[Cu(Ppz)].sub.3] and a polymer, {[[Cu(Ppz)].sub.3][[CuCN].sub.3]} both containing the [Cu(Ppz)].sub.3] entity as a building block are described. The products are obtained by solvothermal reactions of 4(pyrid-4'-yl)-3,5-dimethylpyrazole (HPpz) with CuBr in two mixed solvents, N[H.sub.3]*[H.sub.2]O/EtOH and N[H.sub.3]*[H.sub.2]O/MeCN.

The article studies two domino annulation strategies for construction of benzoxazole ring via domino inter/intramolecular copper-catalyzed cross-coupling using 1,2-dihaloarenes and primary amides and one-pot domino acylation of 2-bromoanilines with acyl chlorides. The one-pot domino acylation was found to be more practical method for synthesis of benzoxazole ring.

The magnetic field effect (MFE) on the photoinduced electron transfer (PET) between the [[Cu[(phen).sub.2]].sup.2+] complex and DNA in a homogeneous buffer medium and reverse micelles is studied. The MFE is found to be less prominent in reverse micelles, as compared to the buffer medium.

A single-step, low-temperature and -pressure hydrothermal method is developed for synthesizing a series of silver delafossites (AgB[O.sub.2] (where B = Al, Ga, Sc and In)). The optical band gaps for silver delafossites are larger, visible light absorption is lower and the conductivities are similar or lower than the polycrystalline powder samples of copper delafossites, which are attributed to the scarcity of silver 4d states just below the valence band maximum.

The ordering and interconnection of one-dimensional (1D) dipeptide nanostructures is analyzed by using the two-dimensional (2D) cocrystallization method. 2D cocrystallization and the organic linker terephthalic acid (TPA) have shown that continuous and highly periodic dipeptide arrangements are formed on both the anisotropic Cu(110) and the isotropic Cu(100) surface.

Biphenyl-3,4',5-tricarboxylate is used with Cu(II) for generating a highly porous crystalline material containing both the common binuclear Cu(II) paddlewheel cluster and the exotic trinuclear Cu(II) cluster. This material has displayed relatively high excess gravimetric and volumetric [H.sub.2] uptake.

High-resolution UV photoemission and near-edge X-ray absorption spectroscopy are used for examining the electronic properties of a single layer (SL) of pentacene molecules by either standing up on an aromatic self-assembled monolayer or planar on a bare Cu(111) substrate. The highest-occupied molecular orbital lineshape in the weakly interacting SL has shown a double structure, which is attributed to two nonequivalent molecules in the ordered configuration.

BiCuOS is synthesized at low temperature and pressure by single-step hydrothermal process. Its optical and electrical properties were measured to study the effect of replacing a rare-earth cation with bismuth.

The pillared-layer open three dimensional 4f framework of the hydrothermally synthesized heterobimetallic lanthanide-copper coordination polymers is studied. The optical and luminescent properties of these complexes are investigated using IR spectroscopy.

The article describes a novel copper(II)-catalyzed asymmetric carboamination reaction that involves intramolecular addition of arylsulfonamides across terminal alkenes to provide chiral sultams. This method has also provided access to enantiomerically enriched nitrogen heterocycles.

Several hydrothermal reactions are utilized to synthesize two new organically templated layered copper(I) sulfites. The sulfite anion is found to act as the soft, as well as the hard ligand in these compounds.

The linear and nonlinear optical (NLO) properties of a series of [D.sub.3] [F(II), Ru(II), Ni(II), Cu(II), Zn(II)]octupolar metal complexes featuring the 4,4'-bis[(dibutylamino)styryl]-2,2'-bipyridine ligand are described. These compounds have displayed relatively large first hyperpolarizabilities and two-photon absorption (TPA) cross section values.

The ground state electronic structure of oxidized azurin from Pseudomonas aeruginosa and its optical response are investigated. Results reveal that the unpaired electron spin density is mainly localized on the copper ion.

The assembly and structural characterization of a discrete endo-type disilver(I) complex and a mixture of three-dimensional (3D) copper(I) iodide products derived from a calyx[4]bis(thiacrown) is presented. Rhomboidic Cu-[I.sub.2]-Cu and cubane-type [Cu.sub.4][I.sub.4] units are used for discriminating two exo-coordinated CuI complexes in the mixed product.

Tricoordinate copper(I), silver(I) and gold(I) complexes of a tetraphenylazadipyrromethene ligand are characterized by optical absorption and emission spectroscopy, multinuclear NMR and mass spectrometry. The results have shown that the principal absorption features in azadipyrromethene complexes have resulted from optically allowed intraligand transitions that undergo configuration interaction.

The effects of a thioether donor on the properties and chemistry of copper(I) complexes and on their [O.sub,2] reactivity are studied and compared with closely related copper(i) complexes having a pyridyl ligand donor counterpart. The relevance of the chemistry to copper enzyme [O.sub.2].activation and situations of biological stress involving methionine oxidation are discussed.

Optical absorption and steady-state and time-resolved fluorescence methods are used for examining the photophysical properties of self-assembled [[[Cu.sub.2][(5-OH-bdc).sub.2][L.sub.2]].sub.12]] ([[(5-OH-bdc).sup.2-] = 5-hydroxybenzene-1,3-dicarboxylate and L = dimethyl sulfoxide, methanol or water ligand) hydroxylated nanoballs (OH-nanoball). The analysis has shown that the fluorescence anisotropy of the nanoball is identical to that of free ligand, indicating rapid energy transfer between ligands within the OH-nanoball.