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Combined X-ray (combined + x-ray)
Selected AbstractsEnergy Level Alignment and Interactions at Potential Contacts for Spin Injection into Organic Semiconductors,ADVANCED ENGINEERING MATERIALS, Issue 4 2009Mandy Grobosch The present study provides the interface electronic properties between La0.7Sr0.3MnO3 and two archetype organic semiconductors, CuPc and , -6T using a combined X-ray- and ultraviolet photoelectron spectroscopy. La0.7Sr0.3MnO3 is a ferromagnetic metal and can be used to inject spin-polarized current into organic semiconductors. The energy level alignment depends on the cleaning procedure that is applied to the La0.7Sr0.3MnO3 surface prior to deposition of the organic semiconductor. [source] Alignment of the energy levels and charge injection barriers at interfaces for spin injection: La0.7Sr0.3MnO3 in contact with organic semiconductorsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 5 2008M. Grobosch Abstract For determination of the energy-level alignment at inter- faces between La0.7Sr0.3MnO3 films and two typical organic semiconductors, copper-phthalocyanine (CuPc) and ,-sexithiophene (,-6T) we have performed a combined X-ray and ultraviolet photoemission study. La0.7Sr0.3MnO3 thin films were grown by using the pulsed laser deposition (PLD) technique and subsequently ex-situ cleaned before the organic materials were thermally evaporated. We show that under these conditions the interfaces are free from chemical interaction and are characterized by a short-range interface dipole and large injection barriers. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Re-investigation of the structure and crystal chemistry of the Bi2O3,W2O6 `type (Ib)' solid solution using single-crystal neutron and synchrotron X-ray diffractionACTA CRYSTALLOGRAPHICA SECTION B, Issue 2 2010Neeraj Sharma Single crystals of composition Bi35.66W4.34O66.51 (or Bi8.2WO15.3, bismuth tungsten oxide), within the type (Ib) solid-solution region of the Bi2O3,WO3 system, were synthesized using the floating-zone furnace method. Synchrotron X-ray and neutron single-crystal diffraction data were used to confirm the previously tentative assignment of the room-temperature space group as I41. Fourier analysis of the combined X-ray and neutron datasets was used to elucidate and refine fully the cation and anion arrays for the first time. The mixed cation site M1 is shown to be coordinated by eight O atoms in an irregular cube when M = Bi, and by six O atoms in an octahedron when M = W. The resulting disorder in the average structure around M1 is discussed in the context of experimentally observed oxide-ion conductivity. [source] Ethyl 3-[1-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorin-2-yl)propan-2-ylidene]carbazate: a combined X-ray and density functional theory (DFT) studyACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2010Youssef Arfaoui In the title compound, C11H21N2O5P, one of the two carbazate N atoms is involved in the C=N double bond and the H atom of the second N atom is engaged in an intramolecular hydrogen bond with an O atom from the dimethylphosphorin-2-yl group, which is in an uncommon cis position with respect to the carbamate group. The cohesion of the crystal structure is also reinforced by weak intermolecular hydrogen bonds. Density functional theory (DFT) calculations at the B3LYP/6-311++g(2d,2p) level revealed the lowest energy structure to have a Z configuration at the C=N bond, which is consistent with the configuration found in the X-ray crystal structure, as well as a less stable E counterpart which lies 2.0,kcal,mol,1 higher in potential energy. Correlations between the experimental and computational studies are discussed. [source] 4-(3,5-Dimethyl-1H -pyrazol-4-ylmethyl)-3,5-dimethyl-1H -pyrazol-2-ium dihydrogen phosphate: a combined X-ray and DFT studyACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2010Dipak K. Hazra The molecular structure of the title salt, C11H17N4+·H2PO4,, has been determined from single-crystal X-ray analysis and compared with the structure calculated by density functional theory (DFT) at the BLYP level. The crystal packing in the title compound is stabilized primarily by intermolecular N,H...O, O,H...N and O,H...O hydrogen bonds and ,,, stacking interactions, and thus a three-dimensional supramolecular honeycomb network consisting of R42(10), R44(14) and R44(24) ring motifs is established. The HOMO,LUMO energy gap (1.338,eV; HOMO is the highest occupied molecular orbital and LUMO is the lowest unoccupied molecular orbital) indicates a high chemical reactivity for the title compound. [source] Disordered structure of ZrW1.8V0.2O7.9 from a combined X-ray and neutron powder diffraction study at 530 KACTA CRYSTALLOGRAPHICA SECTION C, Issue 10 2009Xi Chen A novel compound, vanadium aliovalent substituted zirconium tungstate, ZrW1.8V0.2O7.9, was prepared with vanadium substituting tungsten rather than the common zirconium substitution. The structure of the high-temperature phase was refined from combined neutron and X-ray powder diffraction data gathered at 530,K. This phase is the disordered centric modification (space group Pa) and the average crystal structure is similar to that of ,-ZrW2O8. The V atom occupies only a W2 site and charge compensation is achieved through oxygen vacancy, i.e. the oxygen vacancy occurs at only the O4 site. [Atom names follow the established scheme; Evans et al. (1996). Chem. Mater.8, 2809,2823.] [source] N,N -Diethyl- N,-[(E)-4-pyridylmethylene]benzene-1,4-diamine: a combined X-ray and density functional theory studyACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2009Rüdiger W. Seidel The crystal structure of the title compound, C16H19N3, comprises neutral molecules of a dipolar Schiff base chromophore. A density functional theory (DFT) optimized structure at the B3LYP/6-31G(d) level is compared with the molecular structure in the solid state. The compound crystallizes in the noncentrosymmetric space group Pna21 with a herring-bone packing motif and is therefore a potential candidate for nonlinear optical effects in the bulk. [source] | ||||||||||