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Structural and electronic characteristics of KY(WO4)2 (KYW) (010) crystal surfaces have been studied using reflection high-energy electron diffraction (RHEED) and x-ray photoelectron spectroscopy (XPS). The results indicate that the crystal structure and chemical composition of the mechanically polished pristine surface is stoichiometrically well maintained as expected for KYW crystals. Combined measurements of RHEED and XPS as a function of 1.5 keV Ar+ ion irradiation of the KYW (010) surfaces indicate amorphization, partial loss of potassium atoms, and partial transformation of chemical valence state of tungsten from W6+ to a lower valence state, W0 state predominantly, which induces electronic states at the top of valence band. [ABSTRACT FROM AUTHOR]

Optical quality Pb2MoO5 single crystals were grown by the Low Thermal Gradient Czochralski (LTG Cz) technique. The resulting Pb2MoO5 crystals had diameters of 40–50 mm and lengths of ~100 mm. The phase composition of the grown crystals was identified by X-ray single crystal structure analysis; the space group is C2/m and a = 14.2221(11), b = 5.7852(5), c = 7.3262(6) Å, β = 114.168(2)° and Z = 4 (R1 = 0.0336). Pb2MoO5(20−1) substrates were prepared by cleavage, and the surface properties were evaluated by RHEED and AFM. The superposition of wide Kikuchi lines and crystal reflexes was found by RHEED. The AFM measurements indicate a surface roughness as low as ~0.2 nm. Thus, atomically smooth surfaces of Pb2MoO5 were formed by cleavage. [ABSTRACT FROM AUTHOR]

Molybdenum nitride films γ-Mo2N/Si have been fabricated with reactive magnetron sputtering in (N2 + Ar) gas mixture. Phase composition of the films has been defined with reflection high energy electron diffraction. Refractive index and extinction coefficient of γ-Mo2N have been evaluated with laser ellipsometry at λ = 632.8 and 488.0 nm. Upper limit of γ-Mo2N film thickness measurable with laser ellipsometry has been found to be ~80 nm. [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]

X-ray photoemission spectroscopy (XPS) measurements have been executed for TlTiOPO4 to elucidate the general features in the electronic structure of the KTiOPO4 family compounds. The peculiarities of the valence band structure have been discussed for the crystals. The persistence of core level binding energy differences O1s–P2p and O1s–Ti2p3/2 has been detected in TlTiOPO4 and KTiOPO4, which relates well with the constancy of averaged P–O and Ti–O chemical bond lengths in this crystal family. The superstructure ordering of the TlTiOPO4 surface subjected to polishing and annealing has been detected by reflectance high energy electron diffraction (RHEED). From comparison of surface crystallographic properties of TlTiOPO4 and KTiOPO4, the most typical superstructure indices have been revealed. [ABSTRACT FROM AUTHOR]

The high-quality CdWO4 crystal of 80-90 mm in diameter and 180-200 mm long has been grown by Low Thermal Gradient Czochralski technique (LTG Cz). Large area atomically flat CdWO4(010) substrates have been prepared by cleavage. The CdWO4(010) surface is stable in the air up to 600 °C. At higher temperatures, the precipitation of WO3 and W19O55 oxides has been detected by RHEED. [ABSTRACT FROM AUTHOR]