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Full-Text Articles in Physics
Full Multiple Scattering Analysis Of Xanes At The Cd L 3- And O K- Edges In Cdo Films Combined With A Soft-X-Ray Emission Investigation, I. N. Demchenko, J. D. Denlinger, M. Chernyshova, K. M. Yu, D. T. Speaks, P. Olalde-Velasco, Oliver Hemmers, W. Walukiewicz, A. Derkachova, K. Lawniczak-Jablonska
Full Multiple Scattering Analysis Of Xanes At The Cd L 3- And O K- Edges In Cdo Films Combined With A Soft-X-Ray Emission Investigation, I. N. Demchenko, J. D. Denlinger, M. Chernyshova, K. M. Yu, D. T. Speaks, P. Olalde-Velasco, Oliver Hemmers, W. Walukiewicz, A. Derkachova, K. Lawniczak-Jablonska
Environmental Studies Faculty Publications
X-ray absorption near edge structure (XANES) at the cadmium L3 and oxygen K edges for CdO thin films grown by pulsed laser deposition method, is interpreted within the real-space multiple scattering formalism, FEFF code. The features in the experimental spectra are well reproduced by calculations for a cluster of about six and ten coordination shells around the absorber for L3 edge of Cd and K edge of O, respectively. The calculated projected electronic density of states is found to be in good agreement with unoccupied electronic states in experimental data and allows to conclude that the orbital character of the …
Stability And Equation Of State Of A Nanocrystalline Ga-Ge Mullite In A Vitroceramic Composite: A Synchrotron X-Ray Iffraction Study, Kristina E. Lipinska-Kalita, Patricia Kalita, Cedric Gobin, Oliver Hemmers, Thomas Hartmann, Gino Mariotto
Stability And Equation Of State Of A Nanocrystalline Ga-Ge Mullite In A Vitroceramic Composite: A Synchrotron X-Ray Iffraction Study, Kristina E. Lipinska-Kalita, Patricia Kalita, Cedric Gobin, Oliver Hemmers, Thomas Hartmann, Gino Mariotto
Environmental Studies Faculty Publications
Synchrotron x-ray diffraction and diamond anvil cell techniques were used to characterize the phase transformations and to evaluate the structural stability at elevated pressures of a developed nanocrystalline composite. The optically transparent material was built of a germanium oxide-based amorphous host matrix with homogeneously dispersed 13±3 nm Ga-Ge mullite-type nanocrystals, which had a structure similar to the conventional Al2O3-SiO2 mullite. The equation of state of the nanocrystals and the overall structural integrity of the nanocomposite were investigated in quasihydrostatic conditions on compression to 36 GPa and on the following decompression to ambient conditions. The overall …
Equation Of State Of Gallium Oxide To 70 Gpa: Comparison Of Quasihydrostatic And Nonhydrostatic Compression, Kristina E. Lipinska-Kalita, Patricia Kalita, Oliver Hemmers, Thomas Hartmann
Equation Of State Of Gallium Oxide To 70 Gpa: Comparison Of Quasihydrostatic And Nonhydrostatic Compression, Kristina E. Lipinska-Kalita, Patricia Kalita, Oliver Hemmers, Thomas Hartmann
Environmental Studies Faculty Publications
Synchrotron x-ray diffraction and diamond-anvil cell techniques were used to characterize pressure induced structural modifications in gallium oxide. Gallium oxide was studied on compression up to 70 GPa and on the following decompression. The effect of the pressure-transmitting medium on the structural transformations was investigated in two sets of compression and decompression runs, one with nitrogen as a quasihydrostatic pressure-transmitting medium and the other in nonhydrostatic pressure conditions. The x-ray diffraction data showed gradual phase transition from a low-density, monoclinic β-Ga2O3 to a high-density, rhombohedral α-Ga2O3. With the use of nitrogen as a …
Nearest-Neighbor-Atom Core-Hole Transfer In Isolated Molecules, Renaud Guillemin, Oliver Hemmers, D. Rolles, S. W. Yu, A. Wolska, I. Tran, A. C. Hudson, J. Baker, Dennis W. Lindle
Nearest-Neighbor-Atom Core-Hole Transfer In Isolated Molecules, Renaud Guillemin, Oliver Hemmers, D. Rolles, S. W. Yu, A. Wolska, I. Tran, A. C. Hudson, J. Baker, Dennis W. Lindle
Environmental Studies Faculty Publications
A new phenomenon sensitive only to next-door-neighbor atoms in isolated molecules is demonstrated using angle-resolved photoemission of site-selective core electrons. Evidence for this interatomic core-to-core electron interaction is observable only by measuring nondipolar angular distributions of photoelectrons. In essence, the phenomenon acts as a very fine atomic-scale sensor of nearest-neighbor elemental identity.
E1-E2 Interference In The Vuv Photoionization Of He, E. P. Kanter, B. Krassig, S. H. Southworth, Renaud Guillemin, Oliver Hemmers, Dennis W. Lindle, R. Wehlitz, M. Ya Amusia, L. V. Chernysheva, N. L. S. Martin
E1-E2 Interference In The Vuv Photoionization Of He, E. P. Kanter, B. Krassig, S. H. Southworth, Renaud Guillemin, Oliver Hemmers, Dennis W. Lindle, R. Wehlitz, M. Ya Amusia, L. V. Chernysheva, N. L. S. Martin
Environmental Studies Faculty Publications
We have measured the forward-backward asymmetry of photoelectron angular distributions produced in the vacuum ultraviolet photoionization of helium. This asymmetry, a consequence of the breakdown of the dipole approximation, measures the real part of the ratio of the quadrupole and dipole matrix elements. In the autoionization region, the strong energy dependence of the asymmetry permits an experimental separation of the ratio of those magnitudes from their phase difference. We experimentally determined the Fano parameters of the 2p21D2 quadrupole resonance, and report improved values of the width Γ and line profile parameter q from those previously available …
Non-Dipolar Electron Angular Distributions From Fixed-In-Space Molecules, Renaud Guillemin, Oliver Hemmers, Dennis W. Lindle, E. Shigemasa, K. Le Guen, D. Ceolin, C. Miron, N. Leclercq, P. Morin, Marc Simon, P. W. Langhoff
Non-Dipolar Electron Angular Distributions From Fixed-In-Space Molecules, Renaud Guillemin, Oliver Hemmers, Dennis W. Lindle, E. Shigemasa, K. Le Guen, D. Ceolin, C. Miron, N. Leclercq, P. Morin, Marc Simon, P. W. Langhoff
Environmental Studies Faculty Publications
The first indication of nondipole effects in the azimuthal dependence of photoelectron angular distributions emitted from fixed-in-space molecules is demonstrated in N2. Comparison of the results with angular distributions observed for randomly oriented molecules and theoretical derivations for the nondipole correction first order in photon momentum suggests that higher orders will be needed to describe distributions measured in the molecular frame.