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The influence of growth temperature and ion-beam irradiation on magnetic properties and, in perpendicular, on the domain structure and coercivity, H(sub c), is discussed. Magnetic multilayers were deposited on electron transparent Si3N4 windows for the purpose of transmission electron microscopy (TEM) and magnetic transmission x-ray microscopy (MTXM) imaging.

Investigation of the magnetic interaction among particles in the Co-Cr-Ta thin films and Co/Pt ML thin film under canted magnetic field is discussed. The initial curve and the hysteresis loop measured by the hall voltage measurement giving along the perpendicular direction that indicated applied field-direction-dependent interaction in Co-Cr-Ta thin film and field-direction-independent interaction in Co/Pt ML thin film.

Investigation of the magnetotransport properties of Co(sub x)Pt(sub 100-x) alloy films is discussed. It is found that, at low temperatures, skew scattering may be the dominant origin for the extraordinary Hall effect.

The theoretical Kerr spectra of Co/Pt multilayer systems as obtained on a first principles basis including multiple reflections and interferences from all the boundaries in-between the layers are investigated. The propagation of electromagnetic waves in any multilayer system can exactly describe by using either a 2 x 2 matrix(super 2) or 4 x 4 matrix(super 3) formalism.

A report on the fabrication and properties of Co-Pt micromagnets by electrodeposition in optically defined micrometer scale patterns is discussed. It is concluded that the both coercivity and retentivity increase with increasing aspect ratio, due to the combined effect of the decreasing demagnetizing field and the perpendicular crystalline anisotropy of Co-Pt.

The domain structures on prepatterned arrays of dots covered by Co/Pt multilayer after various demagnetization procedures are investigated. The dots coupled by direct exchange when the Pt is deposited with vertical incidence for geometries with large spacing between dots and reduced height.

A biaxial exchange anisotropy phenomenon in PtMn/Ni80Fe20 bilayers grown on a Mo(001) surface on MgO(001) substrate is presented. The result is mainly attributed to the growth of the (110) bicrystal structure of the PtMn/Ni80Fe20 bilayer.

The effects of long-range order (LRO) and short-range order (SRO) of CoCrPt on the magnetic properties of sputtered films are discussed. The LRO and SRO results are consistent with the magnetic properties.

The effects of C-ion irradiation on the exchange field and on the magnetoresistance (MR) ratio of spin valves with PtMn pinning layers are discussed. The effect of C-ion irradiation on phase transformation of PtMn films and its correlation with exchange field is presented.

A systematic study of OR in CoCRPtB/Cr media is performed to explore the mechanism of in-plane magnetic anisotropy. The effects of sputtering process parameters on orientation ratio suggest that in-plane magnetic anisotropy arises from the stress anisotropy induced by the interfacial strain, which originates from the topology of the circumferential textures grooves.

A simple and economical way of fabricating CoPt and FePt nanowires embedded inside an array of empty holes in anodized aluminum disk by electrodeposition is discussed. A trend of perpendicular texture in CoPt nanowires is observed.

The magnetic properties of FePt-Ag nanocomposite films synthesized by annealing multilayers deposited on a MgO(100) substrate y laser ablation are discussed in conjunction with the substrate. The perpendicular magnetic anisotropy is a result of the (001) preferential orientation of FePt grains.

The thermal stability and read and write capability of patterned magnetic islands using a vibrating sample magnetometer (VSM), a magnetic force microscope (MFM), and a quasistatic write/ read tester is investigated. The results indicate that there is a window in the head position over which data could be written on the islands correctly at least 75% of the time.

The ZR doping concentration effects on the microstructural evolution, grain size distribution, as well as on ordering kinetics of FePt alloy films is presented. The detailed grain sized and size distribution analyses showed that these films possessed a smaller average grain size (D) with a narrower distribution compared with the FePt.

Investigation of in situ ordered polycrystalline FePt thin films with MgO underlayer using conventional rf diode sputtering is presented. A detailed investigation by chemical analysis is required for more definitive demonstration of the proposed isolation mechanism.

The initial stages of solid state reaction (SSR) in Al/Pt multilayers are analyzed and the results are compared to those recently obtained by high temperature sequential deposition (HTSD). The diffusion coefficients are comparable to those deduced from the value of the final thickness of the a-Al(sub 2)Pt layer reached during HTSD.

The geometrical structure of the tetraaquo and tetrachlor Pt(II) complexes in aqueous solution are studied by means of X-ray absorption spectroscopies combined with quantum mechanical computations. The axial region of square planar complexes in solution does not present a potential which favors restricted borientation of water molecules, so that no coherent contribution to the X-ray absortption spectra is detected either in the EXAFS or in the XANES spectra.

The synthesis of electrochemical catalysts is illustrated by microfabrication. The activity of Pt-Sn structures fabricated onto Pt toward the electrochemical Sn and Pt-Sn structures by Auger electron spectroscopy, atomic force microscopy, and scanning electron microscopy is evaluated.

A study is conducted on the chemistry and DNA binding of transplatinum complexes, which are found to be antitumor agents. These complexes contain pyridine or quinoline which are ligands and help in producing antitumor active cationic complexes.

A report is presented on the subject that the mercury(II) and platinum (II) compounds are unsymmetrical and contain the covalent donor as well as the acceptor bonds in the same molecule. And a clear picture of the reaction path leading to oxidative addition of an Hg-X bond to platinum(II) is detailed.

Observations of the reactions of platinum (IV) complexes and oximes are presented. These observations were then rationalized by a theoretical study.

The characterization of the main oxidation products of dithiolene-alpha-diimine complexes and the dithiolato-alpha-diimine are explained. In addition to that, the optoelectronic properties of the platinum(II) complexes of both the above types are discussed.

The physiochemical effects of GNF-supported platinum particles on the electrocatalytic oxidation of menthol, when compared with a traditional support medium, Vulcan carbon are explored. Changes in the catalytic mechanism indicate that significant mechanistic changes occur when the carbon support material is tailored in terms of composition, crystallinity, and morphology.

Microporosity and connectivity of ordered mesopores of SBA-15 were studied using nitrogen adsorption and novel methods based on selective pore blocking and on the imaging of inverse platinum replica of ordered mesoporous structure. The complementary pores appear to be stable up to 1173 K, but calcination at 1273 K appears to eliminate them and allows one to obtain the SBA-15 sample with adsorption properties close to those of MCM-41.

The rates of chloride for triphenylphosphine substitution is measured in dichloromethane for a series of cyclometalated [Pt(N-N-C)Cl] complexes containing a number of terdentate N-N-C anioninc ligands, derived from deprotonated alkyl-, phenyl-, and benzyl-6-substituted 2,2'-bipyridines. The liability of chloride in platinum(II) [Pt(N-N-C)Cl] complexes depends very little on the various factors which characterize a cyclometalated ring, such as its size, the nature of the Pt-C bond and number of substituents on the ring.

A Co/Pt multiplayer with strong perpendicular magnetic anisotropy is studied by electron beam evaporation of polarized CoK edge EXAFS. The in-plane polarized EXAFS indicate an abrupt interface structure and the abrupt interface structure is probably a surface equilibrium state and can be trapped in the bulk by subsequent deposition without much interdiffusion.

The synthesis and characterization of ordered intermetallic PtPb nanorods is described. The formation of rodlike morphology is due to the introduction of adatom onto the growing surfaces with strong binding sites for both Pt and Pb atoms along low-index directions.

A synthesis of monodispersed FePt nanorods via confined decomposition of Fe[(CO).sub.5] and reduction of Pt[(caca).sub.2] in a surfactant liquid-crystal mesophase is described. The FePt nanorods have self-assembled into ordered arrays along three-dimensions and directed-assembly under external magnetic field has led to two-dimensional hexagonal ordered arrays, parallel to the substrate.

The competitive aryl-halide and aryl-aryl reductive elimination from a series of (P-P)Pt(IV) complexes is presented. Results reveal that a remarkable selectivity dependence on the ligand's bite angle.

An efficient method is developed for pentannulation by utilizing acyloxy-functionalized pyrans that evolve from readily available propargylic esters. A range of epoxides is utilized and pentannulation is achieved by using Pt[Cl.sub.2] to obtain bicycles containing tertiary stereocenter.

An attempt is made to demonstrate shifts in isolated Pt and Pd complexes wherein products are explained by metal shifts or migrations, where a carbon-bound Rh or Pd exchange positions with a nearby carbon-bound hydrogen. The shifting does not appear to involve acidic intermediates but is sensitive to the environmental polarity, suggesting an increase in polarity during the process.

A study was conducted to demonstrate that trigonal-bipyramidal iron tricabonyl bis(phosphine) complexes trans-Fe(CO)3(P((CH2)(sub n)CH=CH2)(sub 3))2 undergo three-fold intramolecular alkene metathesis and hydrogenation to give cage molecules. Consistent with the design elements appear to have considerably lower rotational barriers than their Fe(CO)3 and [Fe(CO)2(NO)](super +) analogues.

The synthesis, characterization and unusual catalytic properties of Au/Pt dendritic heteroaggregate nanaostructures for oxidation reactions in CO/H2 mixtures are reported. Experiments reveal that in the Pt and Au/Pt heteroaggregate nanostructures, CO oxidation and H2 lightoff are clearly linked, implying enhanced CO tolerance for hydrogen activation.

A general synthesis route to FePt nanoparticles is presented that provides a straightforward and stoichiometrically controlled synthesis. It is possible to produce fcc FePt nanoparticles that can be converted to the fct structure at low temperatures with minimal agglomeration/sintering by using the route proposed with nonadecane as the solvent.

It is shown that both Pt(II) and Pt(IV) can be detected when present together in solution and that their proportions can be determined using the peak-height ratio of XANES spectra. The technique could be used to investigate the rate of reduction of prospective Pt(IV) drugs in tissues and tumors from treated animals.

A study shows that protonation of a series of (diimine)PtMe2 complexes occurs preferentially at Pt as opposed to at methyl ligand. The competitive trapping technique is useful for further insight into how the site of protonation/deprotonation may depend on metal complex structure, solvent, identity of acid, and other experimental parameters.

The syntheses, crystal structures, and electronic properties of acetate- and propionate bridged 1-D [Pt (2.2+)(sub 2)](sub infinity) chain complexes, as the first report of 1-D mixed-valence chains consisting of dinuclear cations, are described. The combined results deny a simpler description of Pt(2.25+)(sub infinity) (formally [Pt(II)3 Pt(III)](sub infinity) for the present systems, and rather support the reported mixed-valency of Pt (2.2+)(sub infinity).

A simple chemical process of assembling FePt nanoparticles with control on assembly thickness and dimension is described. The process can be applied to any sized and shaped substrate thus offering a great potential for FePt-based nanodevice fabrication.

The electron transfer mechanism in the [Pt(NH3)(sub 4)](super 2+) [W(CN)(sub 8)](super 3-) donor-acceptor system was investigated by a series of quantum mechanical calculations, based on the B3LYP hybrid functional and the time-dependent density functional theory algorithm implemented in the Gaussian98 package. It was seen that both solvent and interaction with [W(super V)(CN)(sub 8)](super 3-) destabilize Pt d orbitals, but its presence protects Pt from the solvent interactions.