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In-situ scanning tunneling microscopy in combination with in-situ surface X-ray diffraction, with a particular focus on adsorbate and potential dependent surface relaxation phenomena, is used to study the surface structure of Cu(100) modified by chloride and iodide in an electrochemical environment. The findings suggest a predominantly ionic nature of Cl-Cu bond under the given electrochemical conditions and the electrochemical annealing effect is mediated by weakened Cu-Cu bond.

Oxidative chemisorption and cathodic stripping reductive desorption of iodide have been studied at a smooth polycrystalline gold (Au(poly)) electrode. Potential-dependent surface coverage of iodide has been controlled on the basis of its reductive desoprtion in 0.1 M KOH alkaline media and its quantitative oxidation to aqueous iodates in acidic media. The Au (poly) electrode surface catalyzes the decomposition of [H.sub.2][O.sub.2] to [O.sub.2]. Specific adsorption of iodide on the Au electrode inhibits fully the catalytic decomposition and electrochemical oxidation of [H.sub.2][O.sub.2] as well as the adsorption of unknown impurities and the oxidative degradation of the electrode surface by [H.sub.2][O.sub.2]. A quantitative characterization/detection of [H.sub.2][O.sub.2] at the iodide-modified Au (poly) electrode in the alkaline media has, thus, been achieved. Performance of the electrode toward the detection of [H.sub.2][O.sub.2] with respect to response time and sensitivity as well as operational stability has been evaluated. It has a sensitivity of 0.272 mA [cm.sup.-2] [mM.sup.-1] in amperometric measurements with a detection limit of 1.0 x [10.sup.-5] M [H.sub.2][O.sub.2], and the response time to achieve 95% of the steady-state current is

The new stable low oxidation state arsenic (I) iodide reagent [(dppe) As [l](sub 2) l (sub 7) exhibits chemistry that is considerably different from its As (super III) analogues. The crystal structure of the derivative salts [(dppe) As][(dppe) As (sub 2) l (sub 7) is reported and is compared to that of [(dppe)-As](sub 2)[SnCl (sub 6)]. 2CH (sub 2) Cl (sub 2).

A standard second general catalyst, based on air-stable and commercially available racemic 2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl (BINAP) ligand, in combination with a weak cesium carbonate base is used as a general catalytic system for the efficient amination of aryl iodides. By taking the 'base effect' into account a general protocol for the intermolecular amination of aryl iodides with all types of amines is developed based on a standard Pd-BINAP catalyst, using cesium carbonate as the base.

Syntheses, crystal structures, and properties of four heterometallic iodoplumbates, [(PbCu6I8)(PPh3)6], PbAg2(PPh3)2I4](sub n).[PbI2(DMF)2](sub n), [(Bu4N)(PbCuI4)](sub n), and [Bu4N)(PbAgI4)](sub n) are described. The four unprecedented iodoplumbates brings heterometallic bonding interactions into the common PbI6 octahedral unit.

The useful application of organozinc iodides were examined for the synthesis of nonproteinogenic amino acids. The results from combination of electrospray (ESI)-MS/MS, accurate ion mass measurements, and infrared multiphoton dissociation (IRMPD) spectroscopy employing a free electron laser for the gas phase ion structures of the organozinc cations are also discussed.

The 5-halopyrimidine nucleotides have damaged DNA upon UV-irradiation or exposure to [gamma]-radiolysis via the formation of the 2E-deoxyuridin-5-yl [sigma]-radical. Quenching studies have shown that cross-links are produced by [gamma]-radiolysis and the observations have suggested that aryl iodide C-nucleotide analogues are useful as probes for excess electron transfer and radiosensitizing agents.

A newly developed methodology that affords N-alkyl-2-arylpyrroles and N-aryl-2-arylpyrroles via direct coupling from aryl iodides is presented. The reaction could be enhanced by using anhydrous DMSO as solvent and 5 M excess of pyrrole counterpart and is found to compatible with electron-withdrawing and electron-donating groups on the aryl moiety.

The application of the (2-pyridyl)acetone as a ligand for the copper-catalyzed reactions of phenols with aryl iodides, bromides and chlorides is discussed. The reaction is shown to exhibit excellent reactive selectivity, as well as functional group compatibility.

An efficient and reusable catalyst with PdEDTA immobilized in an ionic liquid brush and a green procedure was developed for coupling aryl iodides and bromides with phenylboronic acid. The reactions conducted in water under aerobic conditions with water-insoluble or even solid aryl halides gave excellent product yields and showed good environmental friendliness and catalyst recyclability.

A highly efficient Cu-catalyzed C-O bond-forming reaction of alcohol and aryl bromides is developed. The transformation is realized by using copper(I) iodide as a catalyst, 8-hydroxyquinoline as a ligand, and [K.sub.3]P[O.sub.4] as a base.

A wide range of diaryl ethers and alkyl aryl ethers are prepared through intermolecular C (aryl)-O bond formation from the corresponding aryl iodides/aryl bromides and phenols/alcohols through Ullmann-type coupling reaction in the presence of a catalytic amount of ([plusmn])-diol L3-CuI complex under very mild reaction conditions. The catalytic system is not only capable of coupling hindered substrate but has also tolerated a broad range of a series of functional groups.

Parallel microscale experimentation is used for developing general conditions for the Suzuki-Miyaura cross-coupling of diversely functionalized primary alkyltrifluoroborates with a variety of aryl chlorides. The conditions obtained are amenable to coupling with aryl bromides, iodides and triflates.

Fluorous aryl and alkyl iodine(III) dichlorides are prepared by reactions of [Cl.sub.2] and the corresponding fluorous iodides. The effect of the structure of the iodine(III) dichloride upon reactivity is studied and the fluorous systems with [R.sub.f8] substituents are superior, but 3-[Cl.sub.2]I[C.sub.6][H.sub.4]COOH is more reactive and has given higher selectivities.

The preparation of crystalline per-O-TBS-[beta]-D-galactofuranose as a new precursor of D-Galf units is described. Anomeric iodination by reaction with TMSI followed by in situ coupling with simple alcohols and glycosyl acceptors is used as a new efficient glycosylation method for assembling D-galactofuranosyl moieties with high [beta]-stereoselectivity.

Several studies are conducted to explain the pH oscillations and the dynamics of the iodate-thiosulfate-sulfite reaction system. The new approach is shown to be extremely helpful for simulations, as it considerably reduced the number of the kinetic parameters.

The studies of the photodissociation dynamics of propyl iodides n-[C.sub.3][H.sub.7]I and i-[C.sub.3][H.sub.7]I near 280 and 304 nm are presented. The observation shows the RC[H.sub.2] deformation vibration of the n-[C.sub.3][H.sub.7] radical to be the most easily excited vibrational mode.

Ultraviolet photoelectron spectroscopy (UPS) is used to study the electronic structures and substituent effects of o-, m-, and p-iodonitrobenzene and the observed bands are interpreted on the basis of empirical arguments and theoretical calculations. The correlation between substituent effects and the relative reactivities of the iodonitrobenzenes is described by the investigation of [pi]- and n-orbital ionization potentials.

The extended X-ray absorption fine structure (EXAFS) spectroscopy is employed to study the characteristics of octakis(DMSO)lanthanoid(III) complexes in the solution and in solid iodides.

Several experiments are conducted to present the crystallographic, as well as the vibrational spectroscopic studies of the octakis(DMSO) (DMSO= dimethylsulfoxide)lanthanoid(III) iodides. The results show that the polarization of the bonds increases in smaller and heavier lanthanoid ions.

The effect of ortho substituents in iodobenzenes on the rate of the abstraction of iodine by cyclohexyl radicals is examined. The stabilization of the transition state, resembling a 9-I-2 iodanyl radical, by electron-withdrawing groups describes a positive sign of the Hammett rho value in the radical abstraction of halogen atoms.

Manganese carbonyl mediates stereoselective photolytic radical addition of alkyl iodides to chiral N-acylhydrazones with tolerance of additional functionality in both coupling partners and excellent flexibility for synthetic planning. The optimization and the expansion of the scope of these reactions, as also studies of stereoselectivity and experimental evidence regarding the mechanism of the reaction are presented.

The kinetics and mechanism of the oxidative addition of MeI to a new type of diplatinum(II) complex containing a bridging bidentate phosphorous ligand and a bridging bidentate nitrogen ligand are studied by spectrophotometry. A double MeI oxidative addition is observed and the classical SN2 mechanism is suggested for both steps.

Two simple and inexpensive systems for copper-catalyzed N-arylations of sulfoximines with aryl bromides and aryl iodides are developed in a study. The novel protocol requires a less cost-intensive ligand/metal salt combination than previously established copper-mediated and palladium-catalyzed reactions, and provides the products in higher yields.

Structural characterization of the binding of two halides, iodide and chloride to transthyretin is performed in which chlorides are known to shield charge repulsions at the tetrameric interface of transthyretin improving tetramer stability of the protein. The refined structures showed iodides and chlorides bound at two of the three halogen-binding sites located at the hydrophobic channel.

The density functional theory (DFT) is used to determine the structures and properties of the respective complexes of Pb(II), to explore the role of Pb(II) ions in the radical formation process. I is also used to set limits on the minimal requirements of organic molecules that can act as building blocks of humic acids in terms of radical formation and behavior under certain characteristic conditions such as Pb binding.

The formation of supramolecular networks with polyiodides with organic-based gold (III) iodides is reported. The systematic incorporation of gold iodide units within polyiodide networks allows modulation of their structural and electronic properties. It is found that the electronically active 1-D mixed-valent gold (I/III) iodide chains are embedded within a hyperpolarizable layer of polyiodides and iodine molecules confirming a remarkable layered structure.

The crystal structure of hybrid tellurium iodide bis(N,N-dymethylanilinium) ditellurium decziodide [C(sub 6)H(sub 5)NH(CH3)(sub 2)](sub2)Te(sub 2)I(sub10) is studied. It is found that this compound represents a solution-processable organic-inorganic tellurium halide composite featuring extensive I...I contacts among the constituent Te(sub2)I(sub10)(super 2-) anions.