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61.
New Oxoferrates(III). On the Knowledge of Na14[Fe6O16] Na14Fe6O16 crystallizes triclinic (P1 ) with a = 11.427, b = 8,271, c = 5.953 Å, α = 109.3, β = 87.7, γ = 111.4°, Z = 1, 2166 independent reflexions, R = 0.051. FeO4 tetrahedra are connected by common cornes forming ?Zweier-Doppel-Ketten”? Effektive Coordination Numbers, ECoN, and the Madelung Part of Lattive Energy, MAPLE, are calculated and discussed. 相似文献
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We have studied the interplay of Andreev reflection and cyclotron motion of quasiparticles at a superconductor-normal-metal interface with a strong magnetic field applied parallel to the interface. Bound states are formed due to the confinement introduced by both the external magnetic field and the superconducting gap. These bound states are a coherent superposition of electron and hole edge excitations similar to those realized in finite quantum-Hall samples. We find the energy spectrum for these Andreev edge states and calculate transport properties. 相似文献
65.
Organic solar cells based on polymer–fullerene bulk heterojunctions were optimised with respect to the short circuit photocurrent by means of optical modelling. Due to interference effects present in the thin film multilayer device, an inverse relation between active layer thickness and photocurrent was predicted and experimentally verified. Optimised photovoltaic devices yield power conversion efficiencies of 4%. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
66.
About Perrhenates. 3 On the Structure of the Mesoperrhenate Na3[ReO5] By tempering powder samples (prepared from mixtures of binary oxides: Na2O2/ReO2 and Na2O/ReO3 respectively, Na : Re = 3 : 1, Ar and O2 atmosphere respectively, 400–450°C, corundum boat) in a closed Ag cylinder (500–550°C, 10 d) yellow single crystals of Na3ReO5, sensitive to moisture, were grown. The compound crystallizes trigonal, space group P31, P32 respectively, with a = 5.544(1), c = 13.580(7) Å, Z = 3, drö. = 4.62 g/cm3. The crystal structure [4-circle diffractometer data, 1091 I0(hkl), AgKα, R = 6.14, Rw = 6.08%] is characterized by “isolated” bipyramids ReO5. Na+ ions are occupying all the tetrahedral (Na2, Na3) and octahedral (Na1) holes of the pseudocubic face centred (c/a = 2.441) Re part of the lattice; resulting in a Na3Re kation framework corresponding to the Li3Bi type of structure. Effective Coordination Numbers (ECoN), the Madelung Part of Lattice energy (MAPLE) and the charge distribution (CHARDI) are computed and discussed. 相似文献
67.
The Crystal Structure of CsTcO4 CsTcO4 crystallizes orthorhombic with a = 5.727, b = 5.921 and c = 14.34 Å. Z = 4, space group Pnma (Nr. 62, I.T.). The metal positions were refined by single crystal data, the oxygen positions first determined: the CsTcO4 structure is a slight distortion of the scheelite arrangement (parameters: see text). The MADELUNG Part of Lattice Energy, MAPLE, ?Mean Effective Ionic Radii”?, MEIR, and Effective Coordination Numbers, ECoN, are calculated and discussed. 相似文献
68.
Oxides of a New Type of Formula: On the Knowledge of K3Ni2O4 and K3Pt2O4 K3Ni3O4, greyblack single crystals, obtained by heating K2O and NaNiO2 [K:Ni = 2:1, 500°C, 7d, Ag-cylinders], crystallizes orthorhombic with a = 6.044, b = 9.049, c = 10.567 Å, Z = 4, space group Cmcm (drö = 3.43, dpyk = 3.32 g · cm?3). Due to four cycle diffractometer data (374 hkl, MoKα, R = 8.6percnt;) a new type of structure is found with wavebands of [NiO4/2] \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^{\rm 1} $\end{document} exhibits the C.N. 6, \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm N}\limits^{\rm 2} $\end{document} the C.N. 4. Effective Coordination Numbers, ECoN, calculated by means of Mean Fictive Ionic Radii, MEFIR, the Madelung Part of Lattice Energy, MAPLE and the magnetic properties are discussed. K3Pt2O4, black single crystals with metallic lustre, obtained by heating KOx (x = 1.55 or 1.88) and Pt (powder) [K:Pt = 4:1,1000°C, lh, 600°C, 2d, Pt-capsules] is isotypic to K3Ni2O4 (four cycle diffractometer data: 458 hkl, MoKα, R = 12percnt;). Cellparameters are a = 6.15, b = 9.27, c = 11.51 Å (single crystal data), drö = 5.79 and dpyk = 5.77 g · cm?3. 相似文献
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