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Mechanisms involved in stabilization of sulfide radical cations through complexation with the peptide bond are described. It is proved that the one electron oxidation by [super .]OH radicals of a simple dipeptide containing two methionine residues leads to efficient formation of the Met(S..N) radicals.

The role of NaOH concentration on the oriented attachment growth kinetics was studied by investigating the crystal growth kinetics of ZnS nanoparticles coarsened less than 100 degree Celsius with NaOH concentration from 2 to 8 M. The findings suggest that the concentration of solute is very important for enhancing the oriented attachment growth rate and achieve exclusively oriented attachment growth of nanoparticles at a large size scale.

A study of the dissociation mechanism of the S-S bond in the [alpha],[alpha']-dinaphthyl disulfide radical anion (NpSSNp.-) in organic solution on the bases of transient absorption measurements and DFT calculations is presented. It was seen that NpSSNp.- undergoes S-S bond cleavage to form NpS and Np[S.sup.-] with a first-order rate constant in the magnitude of [10.sup.6][s.sup.-1] in solution at room temperature.

A study was conducted to observe the quenching effect of the photoluminescence of 1,2,4,5-tetrakis(4-pyridylvinyl)benzene in the presence of CdS colloids stabilized by inverse micelles. An increase in the two-photon absorption cross section and in the two-photon-induced fluorescence intensity was observed for the composite solution when pumped by 740-nm laser irradiation.

Preparation of shape-controlled metastable gama-MnS semiconductor nanocrystals was achieved on a large scale through a simple solvothermal method in the presence of PVP. The optical absorption measurement reveals that these novel architectures exhibit remarkable shift of absorption peak during the course of structural compaction and grain growth.

An extension of the transferable potentials for the phase equilibria united-atom (TraPPE-UA) force field to thiol, sulfide, and disulfide functionalities and thiophene is described. The binary vapor-liquid equilibrium data, as predicted by the TraPPE-UA force field, for the n-butane-(1)+ethanethiol(2) and 1-propanethiol(1)+n-hexane(2) systems show good experiment for the separation factors, however, the overprediction of the pure-component vapor pressure results in somewhat shifted coexistence curves.

A facile hydrothermal procedure capable of aligning CdS nanocrystals on multiwalled carbon nanotubes (MWCNTs) without the use of organic bridging molecules such as cysteamine and carboxylates is described. The particle size of CdS on the MWCNTs could not be easily controlled, the surface coverage, the crystal phases, and the orientation could be altered by manipulating the reaction time and by selecting the appropriate chelating agent.

An electrostatic potential-based methodology is presented to study the nature of Lewis acid sites on molybdenum and ruthenium sulfides. The results obtained suggest that the presence of Lewis acid sites on the MoS2 particles can be the more energetically favorable sites on the S edges with 50% sulfur coverage.

A hydrothermal method is reported for synthesizing high-quality, ultralong, large-scale, single-crystalline Sb(sub 2)S(sub 3) by directly reacting SbCl(sub 3) and Na(sub 2)S(sub 2)O(sub 3) solutions. It is suggested that Sb(sub 2)S(sub 3) nanoribbons can be very promising for applications in solar energy and photoelectronic applications.

The solid solutions in the system zinc sulfide/zinc phosphide were investigated using cyclic cluster model within the semiempirical MSINDO method. The results of cyclic cluster calculations for binding energies of the perfect zinc sulfide and zinc phosphide were presented and compared with the experimental data and a miscibility gap was found at both the ends.

Layered double hydroxide Cd(sub 1-x)Al(sub x)(OH)2(DS)(sub x).3.0H2O (CdAIDS) and a related hydroxide salt compound Cd2(OH)3(DS).2.5H2O (CdDS) where DS stand for dodecyl sulfate sandwiched between two adjacent inorganic layers are synthesized and used as a precursors for CdS nanoparticle growth. The nano-CdS implanted composite exhibits high photocatalytic activity for degradation of the nonbiodegradable rhodamine B under both UV and visible irradiations.

The results of treatment of surface silanol groups with hydrophilic compounds, which enables silica-coated cadmium sulfide nanoparticles dissolved in water/methanol mixture, are examined. The resulting void space like the structure of a jingle-bell is also examined.

Supercrystals of uniform nanrods and nanowires are presented. A convenient method to produce highly uniform ZnS nanorods and nanowires is described.

A cost-effective general procedure is presented to calculate the electron affinities of covalent linkages, which can attach an electron to create a three-electron bond. The ways to make the process more economical and applicable to large molecules are presented.

General laws for the precipitation of ZnS in aqueous mixture of zinc acetate and thioacetamide aqueous solutions is established and succeeded for the first time in establishing a correlation with the growth of films by the so-called chemical bath deposition method. It is showed that the building units both for the film and the precipitate are nanocrystallites formed in the solution.

The infrared reflection absorption (IR-RA) spectra indicate relatively ordered structures in the methylene parts for the C6AzSSC12 and HAzSSC12 self-assembled monolayers (SAMs). IT is observed that the substituent of the azobenzene moieties is also an important factor in regulating the photoreactivity as well as the SAM structures.

The electronic properties of hybrid inorganic/organic thin films are investigated where the inorganic components are monodisperse CdS quantum size particles and the electronic properties of hybrid Langmuir-Blodgett films are studied. In this case, low-energy photoelectron spectroscopy is applied in which the energy of photoelectrons, ejected from the metal substrate or films themselves is measured.

The nature of hydroxyl radical reaction with aryl sulfides is observed to depend strongly on the nature of the substituted group present in the molecule. The fraction of the solute radical cation formed in acidic solution is observed to increase with increasing concentration of acid.

The reaction of FeS(super +) with methane is examined by guided ion beam mass spectrometry and density functional theory employing the B3LYP/6-311+G* level of theory. The lowest-energy path involves a formal 1,2-addition of H3C-H across the Fe(super +)-S bond to generate a CH3FeSH(super +) insertion intermediate.

Formation of intra molecular sigma three-electron-bonded 2 sigma/1sigma* radical cations upon reduction of dialkylsulfinyl sulfides by H-atoms in strongly acidic aqueous medium were studied. The findings indicate that this reaction leads to the formation of an S(super .+) radical cation entity, which coordinates, with the original sulfide moiety to yield the three-electron-bonded 2sigma/1sigma radical cation.

The synthesis of the nanocomposite crystals, (Ag)(sub x)(Ag2S)(sub y) with x < y in micellar media is conducted. The results reveal that the generation of Ag clusters on Ag2S nanocrystal is attributed to the reduction of mobile Ag(super +) ions in the Ag2S nanocrystals by sulfur derivatives.

The stabilization of a disulfide radical anion through formation of a sandwich-type structure involving the respective substituents at the sulfur-sulfur bridge is analyzed. The substituents are shown to be the heterocycles providing the possibility for [pi]-interaction and in contrast to the aliphatic systems it has a higher reducing capacity, which is expressed in the efficient reduction of oxygen by the three-electron-bonded radical anion.

The structures and thermochemistries of carbonyl sulfide (OCS) interacting with one or four water molecules are determined. OCS is observed to interact with low-energy water clusters in each of the complexes with two or more waters.

The temperature dependence of the heterogeneous reaction of carbonyl sulfide (COS) on magnesium oxide (MgO) is examined by using a Knudsen cell reactor and a temperature-programmed reaction apparatus. The results have shown that the initial uptake of COS on MgO is contributed by an absorption process and the steady state uptake is due to a catalytic reaction.

The primary products of the bimolecular free electron transfer (FET) from aromatic sulfides to n-butyl chloride radical cations are a dissociative and metastable radical cation conformers. The electron transfer from aromatic sulfides to the parent radical cations of n-butyl chloride enables a deeper insight into the mechanism of free electron transfer (FET) and allows distinguishing between diffusion and reaction-controlled process.

Pure rotational spectra of five isotopomers of the 1:1 weakly bound complex formed between carbonyl sulfide and trifluoromethane (TFM) was measured using Fourier transform microwave spectroscopy. The experimental rotational constants and dipole moment components are consistent with a structure of [C.sub.s] symmetry in which the dipole moment vectors of OCS and HC[F.sub.3] are aligned antiparallel.

The reactivity and mechanism of omega-bond disassociation in naphthyl phenyl ketones having a phenylthiyl moiety as a leaving group, p-(alpha-napththoyl)benzyl phenyl sulfide (NBPS) and 4-benzoyl-I-naphthylmethyl phenyl sulfide (BNMPS), in solution are explored by laser flash photolysis techniques. Both ketones underwent omega-bond cleavage of the C-S bond to release the phenyl thiyl radical at room temperature.

Ultrafast photoexcited carrier dynamics in CdS nanoparticles prepared by an AOT/n-heptane reversed micelle system are investigated by a femtosecond visible-pump/mid-infrared (IR) probe technique. The results reveal that the photoexcited free electron lifetime monotonically increases as the size decreases, which indicates that the surface trap state is deactivated by the thiol-cap.

Density functional theory studies are carried on the CO adsorption on both hexagonal and triangular clusters and the structures have determined adsorption properties. Hexagonal clusters have preferred monocarbonyl adsorption over dicarbonyl adsorption on the stoichiometric and nonstoichiometric Mo sites at low coverage and dicarbonyl adsorptions have existed at high CO coverage.

Bis(trifluoroaceto) disulfide CF(sub 3)C(O)OSSOC(O)CF(sub 3) is prepared and studied by Raman, photoelectron spectroscopy (PES), and theoretical calculations. It is stated that molecule exhibits the same general trend observed in conformational studies of esters (-C(O)O-) and disulfides (-SS-).

The relationship between electronic- structure properties exhibited by 4d-transition-metal sulfides (TMSs) in connection with hydroesulfurization (HDS) catalytic activity is examined. The electronic structure is studied by means of a periodic density functional approach using a plane-wave basis set and appropriate pseudopotentials.

Novel hierarchical heterostructures formed by wrapping ZnS nanowires with highly dense Si[O.sub.2] nanowires were synthesized by vapor-liquid-solid process. The study indicated that a typical hierarchical ZnS/Si[O.sub.2] heterostructure consists of a single-crystalline ZnS nanowire (core) with diameter gradually decreasing from several hundred nanometers to 20 nm and adjacent amorphous Si[O.sub.2] nanowires (branches) with diameter of about 20 nm.

A catalyst assisted formation of comb-like nanocantilever arrays grown perpendicularly from both sides of pre-synthesized ZnS nanoribbons along [0001] directions by simple post-annealing treatment is described. The formation of nanocantilever arrays is considered to be associated with the preferential chemical etching property of the plusmn(0001) surfaces of ZnS nanoribbons due to surface polarity.

A surfactant-assisted solvothermal approach for the controllable synthesis and evolution of PbS nanocrystal at low temperature is presented. PbS nanocrystals with different morphologies are all obtained with a high yield through precise control of the experimental parameters.

The substitution of cu(super 2+) by Ag(super +) in hydrated Cu(super II)S and [Cu(super II)]3S3 was modeled computationally by density functional theory quantum theory of atoms in molecules, and solvent field methods. The coordination, first-shell and party second-shell molecular structures, and thermochemical data for solvated Cu(super 2+), Ag(super +), Cu(super II)S, [Cu(super II)]3S3, AgCu2S3 and their reactions were obtained.

A study is conducted to investigate the magnetic effects of disulfide bridges on surrounding protons. It is shown that for distances commonly sampled in protein structures, the effect of disulfide on neighboring protons is sizable.

The synthesis of nanowires and nanoribbons having bulk like MoS2 crystal structures is reported. The synthesis relies on the step-edge selective electrodeposition of MaO to form hemicylindrical nanowires on the basal plane of a highly oriented pyrolic graphite crystal, which is followed by the conversion of the nanowires to MoS2 in the H2S at elevated temperatures.

The study aims to extend the post-adiabatic analysis of the interactions of the F, Cl, and O atoms with closed-shell particles. Various trends in the behavior of the first-order post-adiabatic coupling are analyzed, and the optimal ways to estimate the smallness of this coupling are discussed.

The Synthesis and characterization of the thiogermanic acids H4Ge4S10 and H2Ge4S9 are described with the help of Raman, infrared, powder X-ray diffraction. A model preparation method consisting of reacting germanium oxide with liquid hydrogen sulfide containing a trace amount of water is used to form Ge(sub 4)s(sub 10)(super 4-) ions.

A combined matrix IR and density functional theory of group 6 sulfides is investigated as laser-ablated chromium, molybdenum, and tungsten atoms react with discharged sulfur vapor during cocondensation in excess argon. As a result primary reaction product MS2 molecules are identified and other reaction products, including CrS, CrS3, and WS3, are characterized.

Different complexing agents including ethylenediaminetetraacetic acid, triethanolamine and sodium tartrate are used to obtain bismuth sulfide nanorods with different diameters and lengths. It was found that bismuth sulfide nanorods are successfully prepared by a sonochemical method from an aqueous solution of bismuth nitrate and sodium thiosulfate in the presence of complexing agents.