Results 191 to 200 of about 7,785 (240)

Tiling of a Nb(110) surface with NbO crystals nanosized by the NbO/Nb misfit

Physical Review B, 2002
The overlayer covering a (110) face of a Nb crystal annealed at 1500--2000 K in UHV has been studied by Auger electron and photoemission spectroscopies, low-energy electron diffraction (LEED) and scanning tunneling microscopy (STM). This layer, which results from the surface segregation of oxygen dissolved in Nb bulk, corresponds to a thin niobium ...
I. Arfaoui, J. Cousty, H. Safa
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Vacancy filling effect in thermoelectric NbO

Journal of Physics: Condensed Matter, 2015
Using density functional theory, we have systematically explored the 1a and 1b vacancy filling in NbO (space group Pm-3m) with Nb and N, respectively, to design compounds with large Seebeck coefficients. The most dominating effect was identified for filling of 1b Wyckoff sites with N giving rise to a fivefold increase in the Seebeck coefficient.
Denis, Music, Richard W, Geyer, Pascal, Bliem, Marcus, Hans, Daniel, Primetzhofer   +4 more
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The effect of vacancies on the electronic structure of Nbo

Journal of Physics and Chemistry of Solids, 1982
Abstract The crystal structure of NbO is considered as a NaCl structure with 25% ordered vacancies in each sublattice. Self-consistent energy band structure calculations using the augmented plane wave (APW) method have been carried out for a hypothetical NbO with the full NaCl structure and for the structure with the vacancies.
E. Wimmer, R. Podloucky, P. Herzig, A. Neckel, K. Schwarz   +4 more
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The luminescence of K2(NbO)2Si4O12

Journal of Alloys and Compounds, 1992
The luminescence of K2(NbO)2Si4O12 is described and discussed. It consists of a greenish emission below room temperature. The results are discussed in connection with the recently described crystal structure and the nonlinear optical properties of this compound.
G. Blasse, G.J. Dirksen, M.P. Crosnier, Y. Piffard   +3 more
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Superconductivity in the TiO and NbO systems

Journal of Low Temperature Physics, 1972
This paper presents electrical resistivity and superconductivity studies for the B1 (NaCl) structure oxides of titanium, vanadium, and niobium. In samples of nominal composition TiO x , VO x , and NbO x ,x was varied from 0.8 to 1.2.
J. K. Hulm, C. K. Jones, R. A. Hein, J. W. Gibson   +3 more
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Electrical properties of NbO and NbO2

Journal of Physics and Chemistry of Solids, 1969
Abstract The thermoelectric power and electrical conductivity were measured for NbO and NbO2 as functions of temperature at the limiting oxygen activities for the thermodynamic stability of each of the compounds. The electrical properties of NbO2 were essentially independent of oxygen pressure in the temperature range 50–1000°C, and the properties of
James A. Roberson, Robert A. Rapp
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Sintered NbO Powders for Electronic Device Applications

The Journal of Physical Chemistry C, 2011
Wide band gap niobium oxides are particularly important for electronic device applications. Two types of NbO powders were sintered between 300 and 1100 °C. The structural characterization of the pellets, performed by X-ray diffraction measurements and Raman spectroscopy, revealed the appearance of the NbO and T-, B-, and H-Nb2O5 polymorphs, depending ...
Nico, C., Soares, M.R.N., Rodrigues, J., Matos, M., Monteiro, R., Graça, M.P.F., Valente, M.A., Costa, F.M., Monteiro, T.   +8 more
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Boranil and Related NBO Dyes: Insights From Theory

Journal of Chemical Theory and Computation, 2013
The simulations of excited-state properties, that is, the 0-0 energies and vibronic shapes, of a large panel of fluorophores presenting a NBO atomic sequence have been achieved with a Time-Dependent Density Functional Theory (TD-DFT) approach. We have combined eight hybrid exchange-correlation functionals (B3LYP, PBE0, M06, BMK, M06-2X, CAM-B3LYP ...
Chibani, Siwar, Charaf-Eddin, Azzam, Le Guennic, Boris, Jacquemin, Denis   +3 more
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Plasma resonance in TiO, VO and NbO

Journal of Solid State Chemistry, 1970
Reflectance spectra of TiO, VO, and NbO have been recorded. All these oxides show reflectance minima due to plasma edges. The energy corresponding to the reflectance minimum in TiO varies with stoichiometry (in the homogeneity range) and this phenomenon has been related to the transport properties of these oxides.
C.N.R. Rao, W.E. Wahnsiedler, J.M. Honig
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The electronic structure of NbO: Theory and experiment

Solid State Communications, 1978
Abstract Experimental photoelectric- and X-ray emission spectra obtained from NbO are compared with the molecular orbital calculations of NbO 6 10− cluster using X α discrete variational method. The agreement between theory and experiment establishes the validity of the cluster approach to determine the electronic structure of the 4 d ...
M. Erbudak, V.A. Gubanov, E.Z. Kurmaev
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