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A series of unsymmetrical bi- and tetrathiophenes are synthesized with bipyridine and phosphonic acid functional groups. The variation in oligothiophene length and bipyridine substitution position has allowed comparison of the effect of the variables on electronic properties.

The activation parameters presented for intramolecular electron-transfer between ruthenium (II) and cobalt (III) complexes for the thermodynamic contribution of the entropy change for the reaction to the entropy of activation are verified.

The description of the electronic effects, due to the noncovalent host-guest interactions between calix [6] arene and a ruthenium dimer, [[[Ru.sub.3] O[(OAc).sub.6](CO)(ppy)].sub.2]-mu-pz where ppy is 4-phenyl pyridine and pz is pyrazine, is given.

The electrochemical and spectroelectrochemical analysis is done to determine the influence of anions on the IVCT processes in the mixed-valence dinuclear ruthenium and osmium complexes. Results showed significant differences in the two techniques in the order and extent of effects induced by a number of inorganic anions.

The atomic arrangements inside Ru and Os nanoislands spontaneously deposited on Pt(111) electrode surface are determined with electrochemical scanning tunneling microscopy. The structures of the Ru and Os nanodeposits are addressed in terms of removal and insertion of oxygen ions depending on electrode podtential.

A pure ruthenium hydride complex with N-heterocyclic carbene ligand was efficiently generated from the reaction of a second-generation Grubbs ruthenium catalyst with vinyloxytrimethylsilane and unambiguously characterized. This ruthenium hydride complex showed high catalytic activity for the selective isomerization of terminal olefin and for the cycloisomerization of 1,6-dienes.

The electron-rich cyclopentadienylruthenium complex CpRuCl(PPh3)(sub 2) has turned out to be an efficient catalyst for the cyclopropanation of a wide range of norbornenes and norbornadienes with propargylic carboxylates. An efficient cyclopropanation of cyclobutenes is demonstrated, providing the strained bicyclo[2.1.0(super 1,3)]pentane framework.

Individual Ru(4,4'-dicarboxy-2,2'-bipyridine)(sub 2)(NCS)(sub 2) molecules, known as N3, adsorbed on a TiO2 surface are visualized with a scanning tunneling microscope (STM) operated in ultrahigh vacuum. The preferential adsorption of the N3 molecules at the steps is interpreted with the carboxyl groups readily approaching the poorly coordinated Ti atoms at the step edges and this work is the first step for a molecular-scale understanding of well-defined dye-sensitized TiO2 surfaces.

A series of density functional theory (DFT) and wave function theory methods were used in conjunction with a series of basis sets to investigate the influence of the computational methodology on the relative energies of key intermediates and transition states in potential reaction pathways in ruthenium-silylene-catalyzed hydrosilylation reactions. A variety of DFT methods in a modest basis set and B3YLP calculations in a variety of basis sets calculated the key transition in the Glaser-Tilley (GT) pathway to be energetically favored.

The structural and electronic properties of Ru clusters are examined and are crucial to the advancement of technology. Small, nonmetallic ruthenium (Ru(sub n)) clusters are reported to form unusual square and cubic ground-state structures within DFT by treating the exchange-correlation (XC) functional at the level of general-gradient-corrected approximation (GGA).

The formation and structural characteristics of Ru species applied as a cocatalyst on (Ga(sub 1-x)Zn(sub x))(N(sub 1-x)O(sub x)) were examined by scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. Calcination was shown to cause the decomposition of initial Ru3(CO)12 on the (Ga(sub 1-x)Zn(sub x))(N(sub 1-x)O(sub x)) surface to form Ru(IV) species.

The usefulness of intervalence-resonant Raman spectroscopy in exploring the localized-to-delocalized transition in mixed-valence chemistry is demonstrated. The results presented give evidence for vibronic coupling of totally symmetric bridging vibrations of pyrazine to the 'intervalence' charge transfer that confirms a near-delocalized description for the mixed-valence cluster dimer.

Surface plasmon absorption (color) of Au nanoparticles highly depends on its size, shape, and surrounding surface environment, providing a great opportunity for the development of Au nanoparticles as a probe for chemical and biochemical sensing and as a building block for nano-optical devices.

Investigations on the ruthenium porphyrin-catalyzed intramolecular amidation of sulfamate esters and of the first intramolecular aziridation of unsaturated sulfonamides are reported. Bicyclic aziridines up to 87% yield with 100% substrate conversion and high turnover were produced.

Threading behavior of dimeric ruthenium complex was studied. Differences were found in the SDS-induced dissociation kinetics.

The calculations on the geometries and energy barriers for carbon monoxide decomposition on flat ruthenium surfaces through an indirect route are given. The procedures used in the study are explained.

Study was conducted to prepare Ru(II) coordination compounds with long-lived strongly oxidizing, excited states that can be anchored to semiconductor surfaces for applications in dye-sensitized photogalvanic cells. The products of reductive electron-transfer reactions at sensitized semiconductor interfaces are studied.

The black-dye/TiO2 system by electronic absorption and vibrational spectrocopies are characterized. The FT-IR spectroscopic data reveal that black-dye molecules are bound to the Tio2 surface via a bidentate binuclear coordination.

The atomic structure of RuO2.xH2O as a function of water content from x=0.84 to 0.002 using X-ray diffraction and atomic pair density function is studied. The result reveals that RuO2.xH2O is a composite of anhydrous rutile-like RuO2 nanocrystals dispersed by boundaries of structural water associated with Ru-O.

The various oxygen species on the RuO2(110) surface is characterized and compared with those on Ru(0001) in terms of the local absorption geometry, vibrational modes, electronic properties, and kinetics. By the application of new techniques of LEED, high resolution electron loss spectroscopy and density functional theory calculations, new data are collected.

UV-vis, FTIR spectroscopies and cyclic voltammetry were used for characterizing and determining the features of the monolayers at air-liquid interface of the Langmuir-Blodgett films containing a arachidic acid (AA) and [Ru(L)(totpy)(OH2)](ClO4)(sub 2) (L=Ph2AsCH2CH2AsPh2; 4-totpy = 4'-(4-totyl-2,2':6',2'-terpyridine)) complex. The results indicated that the matrix, which was thought as solid as arachidic acid at low pH, with low possibility of dissolving solutes was able to render a fluid behavior even at low areas in terms of the acid depending on the co-spreading material.

A study of photosensitized electron-transfer reactions between trist(2,2'-bispyridine)ruthenium(II) (Ru(bpy)(sub3) (super 2+) and bipyridinium ions are studied. Zeolites not only provide for novel spatial arrangements of molecules but also provide ways to introduce steric constraints and a novel solvation environment.

Dibromomalonic acid (Br2MA) oxidizes the photo excited state of the Ru(bpy)(sub 3)(super 2+) complex producing Br2.the first of these reactions play an important part in the mechanism of photoinhibition of the Belousov-Zhabotinsky reaction.

Nitrogen-incorporated SAPO-11 molecular sieves are synthesized by a secondary synthesis technique at low nitridation temperature (400 degree C) with a starting material of SAPO-11 zeolite doped with two wt % Ru. It was found that nitrogen-containing species had incorporated into framework of SAPO-11 zeolite, in which some N atoms directly bonded to Al and P atoms and formed AlN4, AlN2O2, and PN4 groups.

The early picosecond time scale excited-state dynamics of the paradigm tris(2.2'-bipyridyl)Ruthenium(II) and related complexes are examined by picosecond Kerr-gated time-resolved resonance Raman spectroscopy. Study helps in understanding the fundamental properties of the excited-state in transition metal complexes.

The host-guest chemistry and photoinduced electron-transfer processes are analyzed in the systems containing Ru[(bpy).sub.2] complex covalently linked to viologen as a guest molecule and cucurbit[n]urils (n = 7,8) as host molecules in aqueous solution. Molecular oxygen is used to unlock the dimer and the light driven molecular lock and unlock processes can be repeated many times with good reversibility.

The surface pressure area isotherm measurements show that the complex forms a stable Langmuir film at the air water interface without adding any electrolytes into the subphase. The Langmuir-Blodgett films are studied by UV-visible, infrared, and emission spectroscopies, atomic force microscopy, and cyclic voltammetry.

An investigation is presented on the role of the central atom X in the structure and reactivity of di-Ru-substituted gama-Keggin poluoxometalates (POMs), gama-[(X(super n+)O4)Ru(super III)2(OH)2(M(sub FM)10O32])(super 8-n) (super -), where M(super FM) = Mo and W, and X = Al(super III), Si(super IV), P(super V) and S(super VI). For both M(super FM) = Mo and W the nature of X is crucial in determining the lower lying electronic states of the polyoxoanions which are in turn significantly impacts their reactivity.

A study on the electronic dyes Ru(tcterpy)(NCS)3 and Ru(dcbpy)2(NCS)2 absorbed from solution onto nanostructured TiO2 is studied. Ru(dcbpy)2(NCS)2 is investigated in its acid (N3) and in its 2-fold deprotonated form (N719) having tetrabutylammonium as counterions.

Dynamics of interfacial electron transfer (ET) in the ruthenium-polypyridyl complex [{bis(2,2'-bpy)-(4-[2-(4'-methyl-2,2'-bipyridinyl-4-yl)vinyl]benzene-1,2-diol)} ruthenium (II) hexafluorophosphate] (Ru-cat)-sensitized TiO(sub 2) nanoparticles is investigated. It is observed that Ru-cat is coupled strongly with the TiO(sub 2) nanoparticles through its pendant catechol moiety.

A series of conjugated polymer-redox polymer hybrids based on the complexation of poly-(bibenzimidazoles) with bis-(2,2'-bipyridyl)Ru(super 2+) and bis-(2,2'-bipyridyl)Os(super 2+) is prepared to investigate the effects of electronic communication between metal centers through the conjugated backbone.