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The method used for obtaining real-time in situ infrared reflection-absorption spectra of any reproducibly reversible process applied to reveal the time-dependent coverages of adsorbates during the low-temperature oscillatory regime of the NO + CO reaction on Pt{100} is presented. The results indicate a significant role for the nonreactive displacement of NO by CO not included in this model.

A three-channel cross-reactive sensor array based on vapoluminescent platinum(II) double salt materials has been characterized. Two arrays were studied, one consisting of [Pt[(CN-cyclododecyl).sub.4]][Pt[(CN).sub.4]] (1), [(phen)Pt[(CN-cyclohexyl).sub.2]][Pt[(CN).sub.4]] (2), and [Pt[(CN-n-tetradecyl).sub.4]][Pt[(CN).sub.4]] (3) materials, where phen = 1,10-phenanthroline, and a second array that has compound 3 replaced by the mixed double salt material [[(phen)Pt[(CN-cyclododecyl)Cl)].sub.2][[(phen)Pt[(CN- cyclododecyl).sub.2]].sub.2][[Pt[(CN).sub.4]].sub.3] (4). Compounds 2, 3 and 4 are characterized here for the first time. Inclusion of solvent vapors into these materials often leads to dramatic shifts in their solid-state absorption and luminescence spectra. In these studies the arrays were exposed to a set of 10 test solvent vapors to determine the ability of each cross-reactive array to give reproducible vapoluminescent spectra characteristic of each solvent vapor. It was discovered that temperature programming between solvent vapor exposures greatly improved the reproducibility of the luminescence spectra obtained. A statistical analysis of three-dimensional resolution factors between pairs of solvent clusters in principal component space supported this assertion. The success of the temperature programming protocol was limited by the thermal stability and the sensitivity to low background water vapor levels of some platinum(II) double salt materials. The ability of the cross-reactive sensor array to differentiate between two different solvent vapors over a large concentration range was also investigated. Acetone and methanol were found to occupy two distinct regions of the three-dimensional principal component space. Detection limits for acetone and methanol were estimated from the principal component analysis as 75 and 6 g/[m.sup.3], respectively.

The frequencies of several new platinum nitride species produced by the reaction of laser-ablated platinum with pure nitrogen is calculated with the density functional theory in addition to the complexes observed in earlier thermal atom studies. Results revealed that absorptions are observed for PtxNN, PtNN(super -), Pt(NN)(sub 2)(super -) and Pt(NN)2 in solid argon and neon.

Experimental and calculated spectra for palladium deposited on Pt(111) are compared in order to elucidate the possible adsorption site and to interpret the main features of the experimental spectra. The study concluded that the combined use of spectoelectrochemical and first principles calculations is a promising and powerful tool for the interpretation of complex electrochemical interfaces.

The adsorption of cyanide on the Pt(111) surface by dissociation of acetonitrile CH3CN is examined by using sum-frequency generation (SFG) and cyclic voltammetry. The results reveal that bands near 1860 and 2073 cm(super -1) in sum-frequency generation (SFG) spectra generate from adsorbed CO, produced by oxidation of CH2CN vapor at the hot Pt crystal.

195Pt NMR was used to investigate the effects of different ligands electrochemically adsorbed onto carbon-supported nanoscale Pt particles.

The Hg(super 2+)- and HgCl(super +)- assisted aquations of a series of platinum(II) chloride complexes and the reverse chloride transfer from HgCl2 and HgCl(super +) to platinum are assessed. Transient metal-metal bonded Pt-Hg adducts characterized by their stability constants and electronic spectra are observed for Hg(super 2+) but not for HgCl(super +) and these adducts are probably not intermediates along the reaction coordinate.

An analysis of the mechanism of C-H activation at a cationic platinum (II) complex with a bidentate nitrogen ligand using quantum chemical density functional theory methods is presented. The main impact of a Lewis basic solvent is to stabilize platinum (IV) series relative to platinum (II).

Attention is concentrated on platinum(IV) compounds due to their lower toxicity and possibility of oral administration in cancer chemotherapy. Platinum(IV) compounds with neutral, nonfunctionalized carbohydrate ligands without anchor groups have recently been synthesized and characterized. The first platinum(IV) compounds with neutral pyranoside ligands, coordinated by two hydroxyl groups, 2-OH and 4-OH, and by the acetal oxygen atom of the pyranose ring of the carbohydrate, are reported.

The electrochemical formation of contacts between platinum or gold electrodes with the organic charge-transfer salts tetrathiafulvalenium bromide (TTFBr(sub x), x = 0.74-0.79) or bis(tetramethyltetraselenafulvalenium) perchlorate ((TMTSF)2ClO4) was investigated. To this end, conducting crystals of the charge-transfer salts were examined. The needle-shaped crystals were prepared between pairs of platinum or gold electrodes by oxidative electrodeposition. An electrical connection resulted when a crystal growing from one electrode encountered the second electrode.

There has been increased interest in chiral inorganic compounds, particularly in enantiomeric catalysis, supramolecular chemistry and bioinorganic chemistry. Previously the synthesis of chiral thienylpyridine ligands substituted with bicyclic aliphatic groups, has been proposed. The crystal structure of a platinum(II) complex Delta-Pt(th5,6capy) is presented.

Pt(PFsub3)sub4 is a good chemical vapor deposition (CVD) precursor for the deposition of platinum. It loses PFsub3 at temperatures nearing 200 degrees C, yielding a cluster, PTsub4(PFsub3)sub8. Fourier transform cyclotron resonance mass spectrometry confirms the composition, although the structure is unknown. Platinum metal is yielded at higher temperatures, and a quantity of PFsub3 gas. Ligands such as P(OCHsub3)sub3 can lead to extensive replacement of the PFsub3 ligand.

Electron ionization of Ptsub4(PFsub3)sub8 in an FT-ICR mass spectrometer readily generates small platinum clusters. Cluster ions of a given n value can be isolated and reacted with gaseous saturated and aromatic cyclic hydrocarbons. The catalytic dehydrogenation behaviour intermediate between single-atom and bulk platinum was studied, and extensive chemisorption and physisorption occurred, depending upon the particular reagent.

Platinum(II) and platinum(0) starting materials are used to prepare the new diplatinum complexes (Pt2(PMe3)6)(hfac)2 and (Pt2(mu-hfac)(PMe3)4)(hfac). The two complexes have chemically inequivalent platinum centers, with one incorporating a trigonal planar platinum(0) center and the other having a square-planar platinum(II) center. There are two PMe3 ligands in each center. The two platinum atoms are bridged by one of the hfac groups and the other is anionic.

The direct axial interaction of a platinum(II) atom with a Mo2 core via a uniquely designed ligand 6-(diphenylphosphino)-2-pyridonate (pyphos) is studied by nuclear magnetic resonance and Raman spectroscopy. Results indicate that the platinum(II) moiety can be positioned at an axial site of an Mo2 core by using tridentate pyphos ligands to form linear trinuclear complexes.

Mixed-valent octanuclear platinum complexes with acetamidate and 2-fluoroacetamidate as bridging ligands were prepared and structurally characterized. The average platinum oxidation state was determined to be 2.25+ for acetamidate and 2.0822+for 2-fluoroacetamidate. In addition, a new type of interdimer Pt-Pt bonding was achieved between the N4Pt and the N2O2Pt atoms in both compounds. Furthermore, solid state ultraviolet-vis near infrared absorption and photoelectron spectra of the two compounds are presented.

Reactive sputtering method is used for preparing single-phase Cr-doped ZnO film on Pt(111)/Ti/Si[O.sub.2]/Si(100) substrates. The ferromagnetic ordering is explained by the interaction of the localized spins with statically occupied polaron states and the multiferroic behavior has added a dimension to the multifunction of ZnO.

The analysis of consecutive [[super 1]H, [super 15]N] Heteronuclear Single Quantum Coherence (HSQC) NMR spectra of cis-[Pt[Cl.sub.4][([super 15]N[H.sub.3]).sub.2]] has shown the substitution of chloro ligands by aqua/hydroxo ligands in both axial and equatorial positions relative to the non-labile N[H.sub.3] ligands. The substitution has occurred first in the axial position with subsequent substitution occurring in equatorial positions and of the eight possible aquation products only five are seen.

The emission and absorption spectroscopies were employed to study the interaction between gaseous [H.sub.2]S and the surface of several metal-containing oligomers. The data from X-ray absorption revealed a square-pyramidal geometry around the transition metal with [H.sub.2]S in the apical position for the pentacoordinated platinum units.

Magnetron sputtering is used for the fabrication of platinum/titanium bilayer counterelectrodes and the effect of thickness of both platinum and titanium layers on their structural, electrical and electrochemical properties is examined. The studies have shown that the as-prepared titanium layer is almost amorphous and intermetallic phase is formed between platinum and titanium layers.

The structure of a vapochromic Pt([Me.sub.2]bzimpy)][Cl.sup.+] ([Me.sub.2]bzimpy = 2,6-bis(N-methylbenzimidazol-2-yl)pyridine) salt is studied. The studies have shown that the vapochromic behavior of this salt is connected to its tendency to adopt packing arrangements spanning a wide range of metal-metal distances and [Me.sub.2]bzimpy...[Me.sub.2]bzimpy interactions.

The [Pt.sup.II]-mediated 1,3-dipolar cycloaddition of oxazoline N-oxides to nitriles is used for the synthesis of dihydrooxazolo-1,2,4-oxadiazoles. The configurations of the asymmetric atoms of the formed ligands are found to be completely dependent on the substituents of nitriles.

Dynamic [super 195]Pt NMR and the corresponding [super 195]Pt chemical shift trend analysis as a powerful method for the rapid assignment of 52 of the possible 56 ternary [[Pt[Cl.sub.6-m-n][Br.sub.m][(OH).sub.n]].sup.2-] complexes (m, n = 0-6) and their respective geometrical isomers is presented.

The synthesis and chemistry of second-generation dinuclear polyamine-bridged complexes containing 1,2-diaminocyclohexane (dach) are described. It is shown that the stability of cis-geometry complexes might make them very good second-generation polynuclear platinum clinical candidates.

The platinum IV complex, which is nearly non-toxic to testicular cancer cells, displays a significantly enhanced cytotoxity profile when attached to surface of amine-functionalized soluble single-walled carbon nanotubes (SWNTs). The soluble nanotubes internalized the platinum IV compound through endocytosis, providing six times concentration that the untethered complex is able to achieve on its own.

Time-resolved magneto-optical Kerr effect is used for measuring picosecond laser induced precessional dynamics in out-of-plane magnetized [[Co/Pt].sub.n] multilayer films. The damping coefficient has increased with number of Co/Pt repeats, which have resulted from an enhanced interaction between magnons and conduction electrons.

Organonitriles bearing an acidic alpha-methylene group, NCC[H.sub.2]R exhibit two reactive centers known as C[H.sub.2] and the cyano moieties. It is found that in the absence of a coordinating metal site, the methylene group is more reactive than the cyano center toward an acyclic nitrone undergoing deprotonation by the latter reagent to provide a simple and novel stereoselective synthetic route for polysubstituted E-alkenes (cyano-alkenes).

The in situ X-ray absorption spectroscopy, ex situ X-ray fluorescence and X-ray powder diffraction have helped in the analysis of phase segregated nanostructured PtRu anode catalysts in an operating direct methanol fuel cell. The extended X-ray absorption fine structure analysis has showed that the Ru-O bond lengths are shorter than those reported for Ru-O of ruthenium oxides, indicating that the phases in which the Ru resides in the catalysts are not similar to oxides.

The structure of (eta(super 2)-diphenylacetylene)Pt(PPh3)2 and those of its dichloromethane and benzene solvates, are determined by X-ray crystallography and the chemical shift (CS) tensors of the (super 13)C-labeled carbons is investigated by NMR spectra. DFT calculations of these CS tensors are in close agreement with the experimental values and the measured carbon CS tensors are strikingly similar to those of the alkenyl carbons in trans-Ph(H)C=C(H)Ph and a theoretical discussion is presented.

An attempt is made to focus on the modulation response of resonant-cavity light-emitting diodes (RCLEDs). The RCLED has an AlInGaP multi-quantum-well active layer that was embedded into AlGaAs-distributed Bragg reflectors to form a one-wavelength optical resonator.

The vibrational properties of mesoporous (SBA-15) were investigated by deep ultraviolet (UV) Raman and infrared spectroscopies with and without the presence of platinum nanoparticles in the mesopores that were incorporated by sonication. The D2 feature in the UV-Raman spectra decreased with increasing Pt loading, which is attributed to interactions of the Pt nanoparticles with the silica surface.

Carbon nanotube (CNT)-supported Pt nanoparticle catalysts are synthesized in supercritical carbon dioxide (scCO2) using platinum(II) acetylacetonate as metal precursor. The structures of the catalysts are characterized with transmission electron micrograph (TEM) and X-ray photoelectron spectroscopy (XPS) TEM images show that the platinum particles' size in the range of 5-10 nm.

A simple method used to prepare nanostructured PtRu/C catalysts by metastable water-in-soil pseudomicroemulsion of water solution/sodium dodecylbenzene(NaDDBS)/n-butanol/cyclohexane/Cabot Vulvan XC-72 carbon powder is reported. These catalysts are found to be nanosized and inherit the Pt-face-centered cubic structure with Pt and Ru mainly in the zero valence oxidation state.

The vibrational spectra of CO adsorbed on Ru-modified Pt(100) surfaces prepared by chemical vapor deposition were investigated by time-resolved infrared reflection adsorption spectroscopy in ultrahigh vacuum (UHV). For all surfaces and CO exposures examined, the total integrated area under the two CO spectral features remained fairly constant and equal in value to the corresponding areas found for bare Pt(100).

A method of imaging nanometer metallocatalysts formed by photosynthetic precipitation of the water-soluble transition-metal compounds [PtCl(sub 6)](super 2-) and [RuCl(sub 6)](super 2-) is reported. The use of this method can potentially create nanometer-sized Pt and/or bimetallic catalysts on biomembranes and molecules at pH 7 and room temperature with preservation of the biological function of the molecules.

Reaction kinetics measurements of the water-gas shift reaction are conducted at 373 K on Pt/Al2O3 in vapor phase to investigate the effects of CO, H2, and H2O partial pressures. Results of in situ ATR-IR studies conducted in vapor phase under similar conditions suggest that the Pt surface coverage by adsorbed CO is high, leading to a negligible effect of the CO pressures on the rate of reaction.

A detailed mechanism of the redox reaction between [Pt(sub IV)Cl(sub 4)(dach)] and 3'-d(guanosine monophosphate) (3-dGMP) is proposed. The Pt(super IV) complex blinds to N7 of guanine in cGMP, 9-Mxan, 5'-d[TTGTT]-3', and 5'-d[TTTTG]-3', but no subsequent transfer of electrons occurs in the reactions.

The adsorption of cyclopentene on Pt(111) and ordered Pt(sub n)Sn/Pt(111) surface alloys are examined by using high-resolution electron energy loss spectroscopy as well as ab initio density functional theory calculations. On the Pt(11) and the respective surface alloys, a di-sigma bonding of cyclopentene is found both experimentally as well as in the DFT calculations.

Multisegment Pt-Ni nanorods were prepared by sequential electrodeposition of Pt and Ni into nanoporous anodic aluminum oxide membranes and characterized by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The overall rod length and the total Pt segment length for different nanorods were kept at 1.6 (mu)m and 530 nm respectively by controlling conditions used in the galvanostatic electrodeposition.

Spectra obtained by electrochemical infrared reflection absorption spectroscopy (EC-IRAS) for carbon monoxide (CO) adlayers formed by partial CO dosing on various ruthenium-decorated platinum nanoparticle films are reported. It is mainly due to the difficulty in preparing monolayer-level films of metal nanoparticles exhibiting near-ideal IRAS as well as electrochemical properties.

A report is presented on the synthesis of the platinum(IV) complexes prepared by the oxidation of the platinum (II) complex with H2O2. Platinum (IV) analogue is important in the preparation of the new antitumor platinum complexes.

Pt(II) oligothienyl complexes [L.sub.2]Pt[(3T).sub.2] as consistent models for catalytically active Ni- or Pd-intermediates are fabricated. The two-step reaction establishes a novel homocoupling method of oligothiophenes.

The electro-oxidation of methanol on platinum by in-situ surface enhanced infrared absorption spectroscopy with the Kretschmann ATR configuration is explained. It is found that formate should be included as a reactive intermediate in the non-CO path in the reaction of the methanol electro-oxidation.

A new series of platinum-acetylide oligomers has been synthesized by an iterative-convergent approach. Absorption and photoluminescence spectroscopy of the oligomers provide considerable insight into the extent of delocalization in the singlet and triplet excited states in Pt-acetylide materials.

A study was conducted to characterize the structure of cyanide-bridged trinuclear complexes carrying square-planar platinum at their centers. Results indicate that their chemical building blocks are composed of cis- and trans-PtL2X2, Cp(dppe)FeX, Cp(PPh3)2RuX (with X=Hal or Cn), Pt(CN)42- and Fe(CN)63-. Data gathered by the infrared (IR) and ultraviolet-vis-near-IR spectroscopes and cyclic voltammograms further show that there are electronic interactions between the outer metal atoms along the linear M-CN chains containing transfigured platinum.