No abstract available

No abstract available

[en] Non-commensurability on the boundaries of adjacent structural layers (rods, blocks) represents an important structure-building principle for several structural families of complex lanthanide sulfides. In the layer-misfit sulfides 'ABS₃', pseudo tetragonal layers with lanthanide ions alternate with octahedral layers or trigonal prismatic layers. Among more complex, fragment-recombination structures based on similar layer strips, a family of derivatives of the structure of Yb₃S₄, or structures that represent anti-(out-of-)phase modulated non-commensurate layer sequences, as well as lanthanide sulfosalts (with bismuth and antimony) are described in some detail. Layer-match modes, their relationships to the ratios of cation radii, and relations to simpler archetypal structures are analysed. 41 refs., 2 tabs., 19 figs

No abstract available

[en] The crystal structure of Θ-Yb₂S₃, crystallizing in the Mn₂O₃ structure type, is refined by X-ray diffraction analysis. Interatomic distances and valence angles are calculated. Using the concept of a space filling up degree (Ψ=ΣV_i/V_cell), the boundaries of this structure type stability, as well as possibilities of transition into another structure type are determined

[en] Initial stages of Yb-Si (111) interface formation were studied by means of thermodesorption spectroscopy, flux modulation and slow electron diffraction. The structure of the adsorbed films and ytterbium silicide films, as well as, kinetics of Y B atom desorption were studied within wide range of coatings. Temperature range where ytterbium silicide decomposes and activation energy of this process are determined for ytterbium silicide

[en] Heavy fermion/Kondo behavior among rare earth intermetallics is believed to originate from the proximity of the 4*f* states to the Fermi level in them. As a result the 4*f* electron fluctuates between the 4*f* level and the valence band giving rise to valence instability. Such a phenomenon is at the heart of interesting and varied ground states like nonmagnetic Kondo singlet state, mixed valent state, non-Fermi/Fermi liquid state etc. The formation of Kondo singlet state at low temperatures is marked by the 'promotion' of 4*f* spectral weight to the Fermi surface giving rise to its expansion

[en] We have begun building the ''Mercury'' laser system as the first in a series of new generation diode-pumped solid-state lasers for target physics research. Mercury will integrate three key technologies: diodes, crystals, and gas cooling, within a unique laser architecture that is scalable to kilojoule and megajoule energy levels for fusion energy applications. The primary near-term performance goals include 10% electrical efficiencies at 10 Hz and 100 J with a 2-10 ns pulse length at 1.047 (micro)m wavelength. Currently, this review concentrates on the critical development and production of Yb:S-FAP crystals. After solving many defect issues that can be present in the crystals, reproducibility is the final issue that needs to be resolved. We have enlisted the help of national experts and have strongly integrated two capable commercial crystal growth companies (Litton-Airton/Synoptics and Scientific Materials) into the effort, and have solicited the advice of Robert Morris (retired from Allied Signal), a recognized international expert in high temperature oxide growth

[en] The YbH₂P₃O₁₀ structure has been studied. Its crystals have been produced by heating mixture of H₃PO₄:K₂CO₃:Yb₂O₃ taken in the molar ratio 30:5:1 at 480 deg C. YbH₂P₃O₁₀ is shown to crystallize in the monoclinic crystal system with the cell parameters a = 5.617(2), b = 6.666(2), c = 10.011(3) A. The Yb atoms are surrounded by 6 oxygens. A symmetric configuration of the P₃O₁₀^5- tripolyphosphate anion has been established

[en] This communication reports the use of a pyrolytic graphite coated tube, lined with tantalum-tungsten, and a local made atomic absorption spectrometer (Model WFD-Y3) for the determination of small amount Yb in pure Y₂O₃ and mixed rare earth oxides. It is found that the method proposed is sensitive, reproducible and simple in manipulation. Even as low as 0.2 μg Yb in one gram sample (n x 10^-7) can be determined directly without pre-concentration. It is found experimentally that the optimum condition for drying is at 150 deg C. for 20 sec, ashing at 1000 deg C. for 20 sec and atomization at 2770 deg C. for 12 sec. Within the range 1.0-18ng Yb/ml the calibration curve of Yb is linear. Before injecting into the tube, the acidity of the sample solution should be ajusted to 0.1 to 2 M with nitric or hydrochloric acid. For 5ng Yb/ml, Al(III), Ca(II) and La(III) interference, when their amount present is 50 μg/ml or more. On the other hand, Cu(II), Fe(III), Mg(II), K(I) and Y(III) in amount up to 1 mg/ml do not interfere