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The arc vaporization of carbon rods in a helium atmosphere performed in the presence of small quantities of pyrrole produces not just nitrogen-doped fullerenes, but also the surface of the carbon rods become coated with a layer of a nitrogen-doped carbon. N1s spectra indicate a nonuniformity in the distribution of nitrogen atoms relative to carbon. These data agree with a model in which substitution of nitrogen occurs at the domain boundaries of the graphitic particles.

The development and the formation of Mo contacts to CuInSe2 was investigated using synchroton radiation soft-x-ray photoemission spectroscopy. The results showed that Mo reacted with the CuInSe2 during the deposition process, producing In islands and a MO-Se interfacial phase. The Mo/n-CuInSe2 interface was observed to be ohmic with a maximum Schottky barrier height less than or equal to 0.2 eV. The interface consisted ofan extended region of reacted and interdiffused species.

Sulfur-containing carbon rods were prepared via arc vaporization of graphite in the presence of thiophenes. X-ray diffraction, conductivity and x-ray photoemission spectroscopic measurements were used to investigate the changes in the structural and electronic characteristics caused by the presence of S in graphite. Results demonstrate that S incorporation induces a shift of the valence band toward the Fermi level.

The x-ray photoelectron spectroscopy technique is employed to analyze the surface current reduction observed in the (211) oriented [Cd.sub.0.46][Zn.sub.0.04][Te.sub.50] crystals by Ar bombardment. The Ar plasmas are shown to be extremely beneficial in changing the surface chemistry of the crystals.

Several studies are conducted to explain the localized surface plasmon resonance enhanced magneto-optical activities of the core-shell Fe-Ag nanoparticles. The exploitation of these properties is shown to be extremely beneficial in enhancing the sensitivity of these nanoparticles.

The surface of the layered III-VI chalcogenide semiconductor GaTe is subjected to various chemical treatments used in device fabrication to determine the effect of the resulting microscopic surface composition on transport properties. The measurements are correlated to understand the effect of surface chemistry on the electronic structure at these surfaces with the aim of minimizing the surface leakage currents for radiation detector devices.

The measurements of the pair creation energy and of the drift mobility of carriers in two chemical vapor deposition (CVD) diamond crystals are reported. The data from measurement shed light on the outstanding electric properties and the enormous potential of diamond in ultrafast x-ray detectors.

X-ray photoemission was used to study the valence band electronic structure and surface chemistry of lanthanum calcium oxoborate. The valence bands were dominated by B and O 2(sub p) states that hybridize with the La 5d states and La 5(sub s) and 5(sub p) multipet splitting was evident.

The results of a systematic study of the 3s and 3p outer core-level multiplet splitting as a function of Mn cluster size, nuclearity and ligand type are presented. Results show that the Mn 3p final-state branching ratio changes as the Mn core size and trapped-valence oxidation state-increases.

The composition and the structure of ytterbium doped strontium fluoroapatite (Yb:S-FAP) are investigated with an x-ray photoemission (XPS) and x-ray photoabsorption (XAS). The formation of Yb(super 3+) - O(super 2-) complexes enhances the both dipole allowed Yb 4d(right arrow)4f and super-Coster-Kronig transitions.