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Titanium dioxide (anatase, a-TiO) films have been prepared by electron beam sputtering of a TiO target in reactive atmosphere and their structural, microstructural, and optical properties were evaluated by reflection high- energy electron diffraction (RHEED) and x-ray diffraction (XRD) analyses, atomic force microscopy (AFM), and spectroscopic ellipsometry (SE). Different reflection models for determination of film optical parameters were tested and compared. The dispersive optical parameters were defined using the Tauc-Lorentz model by SE in the photon energy range of E = 1.12-4.96 eV. The films were transparent at E < 3 eV, but noticeable absorption was detected at E > 3 eV. The bandgap was estimated at the level of E ≈ 3.44 eV. [ABSTRACT FROM AUTHOR]

The optical properties of the highly-textured VO thin-films grown on Si(100) by sputter-deposition at various oxygen reactive-pressures were investigated in detail. The profiles of the optical constants, namely the refractive index and extinction coefficient, of VO films were evaluated in the photon-energy range of 1-5 eV. At photon-energy above 2.5 eV, the dispersion behavior in optical constants is explained based on Lorentz-Drude model. The refractive index dispersion fits to a Cauchy's relation at photon-energy below 2.5 eV, where the VO-film is mostly transparent. The optical transitions across the bandgap occur at energy ∼2.5-3.2 eV depending on the VO growth conditions and film-microstructure. The highly-textured and c-axis oriented VO-films, fabricated under optimum conditions of temperature and oxygen partial pressure, exhibit excellent optical characteristics similar to VO single crystals. [ABSTRACT FROM AUTHOR]

We have prepared h-MoO3 nanocrystals in the form of well-faceted straight hexagonal rods with an aspect ratio of l/d ≃ 60. The nanocrystals have been characterized by x-ray diffraction, scanning and transmission electron microscopy, and IR/Raman spectroscopy. Their phase composition has been determined, and their morphology and spectroscopic properties have been studied in detail. [ABSTRACT FROM AUTHOR]

A study of the surface structure and electronic properties of (010) KGd0.95Nd0.05(WO4)2 (Nd:KGW) using RHEED analysis and XPS is presented. It is shown that Nd doping has a negligible effect on the core levels of the basic elements. A bombardment of the Nd:KGW crystal with 3-keV Ar ions results in surface amorphization accompanied by the generation of tungsten ions in lower valence states. [ABSTRACT FROM AUTHOR]