Photoelectron Angular Distributions Of Ultrathin NI/CU(001) Films

AbstractWe present measurements of the evolution with film thickness of the 3d electronic states at the Fermi energy of ultrathin Ni films. The morphology and thickness of the films is determined from x-ray photoelectron spectroscopy. x-ray photoelectron diffraction and x-ray magnetic linear dichroism using synchrotron radiation. Photoelectron angular distributions were measured using an ellipsoidal mirror analyzer. Even at submonolayer Ni coverages, the 3d electronic states exhibit bulk-like properties. This is attributed to the short screening length of electrons in metals, the localization of the 3d electrons, the similarity of the Ni and Cu ion cores, and finally the interaction with the underlying fcc periodic potential.

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Imaging molecular structure through femtosecond photoelectron diffraction on aligned and oriented gas-phase molecules

Faraday Discussions ◽

10.1039/c4fd00037d ◽

2014 ◽

Vol 171 ◽

pp. 57-80 ◽

Cited By ~ 30

Author(s):

Rebecca Boll ◽

Arnaud Rouzée ◽

Marcus Adolph ◽

Denis Anielski ◽

Andrew Aquila ◽

...

Keyword(s):

Gas Phase ◽

Angular Distributions ◽

Nanosecond Laser Pulse ◽

Nanosecond Laser ◽

Time Resolved ◽

Pump Probe ◽

X Ray ◽

Photoelectron Diffraction ◽

Gas Phase Molecules ◽

Photoelectron Angular Distributions

This paper gives an account of our progress towards performing femtosecond time-resolved photoelectron diffraction on gas-phase molecules in a pump–probe setup combining optical lasers and an X-ray free-electron laser. We present results of two experiments aimed at measuring photoelectron angular distributions of laser-aligned 1-ethynyl-4-fluorobenzene (C8H5F) and dissociating, laser-aligned 1,4-dibromobenzene (C6H4Br2) molecules and discuss them in the larger context of photoelectron diffraction on gas-phase molecules. We also show how the strong nanosecond laser pulse used for adiabatically laser-aligning the molecules influences the measured electron and ion spectra and angular distributions, and discuss how this may affect the outcome of future time-resolved photoelectron diffraction experiments.

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X-ray magnetic linear dichroism

Physics Subject Headings (PhySH) ◽

10.29172/6c0dfaf1778e440fb99aad8cbf63c92a ◽

2018 ◽

Keyword(s):

Linear Dichroism ◽

X Ray ◽

Magnetic Linear Dichroism

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Pore Modification and Phosphorus Doping Effect on Phosphoric Acid-Activated Fe-N-C for Alkaline Oxygen Reduction Reaction

Nanomaterials ◽

10.3390/nano11061519 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1519

Author(s):

Jong Gyeong Kim ◽

Sunghoon Han ◽

Chanho Pak

Keyword(s):

Phosphoric Acid ◽

Photoelectron Spectroscopy ◽

Structural Changes ◽

Electronic States ◽

Nitrogen Adsorption ◽

Reduction Reaction ◽

Phosphorus Doping ◽

X Ray ◽

Precious Metal Catalysts ◽

Adsorption Desorption

The price and scarcity of platinum has driven up the demand for non-precious metal catalysts such as Fe-N-C. In this study, the effects of phosphoric acid (PA) activation and phosphorus doping were investigated using Fe-N-C catalysts prepared using SBA-15 as a sacrificial template. The physical and structural changes caused by the addition of PA were analyzed by nitrogen adsorption/desorption and X-ray diffraction. Analysis of the electronic states of Fe, N, and P were conducted by X-ray photoelectron spectroscopy. The amount and size of micropores varied depending on the PA content, with changes in pore structure observed using 0.066 g of PA. The electronic states of Fe and N did not change significantly after treatment with PA, and P was mainly found in states bonded to oxygen or carbon. When 0.135 g of PA was introduced per 1 g of silica, a catalytic activity which was increased slightly by 10 mV at −3 mA/cm2 was observed. A change in Fe-N-C stability was also observed through the introduction of PA.

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Evidence for the Photoemission Nature of Gd 4f Resonant Photoemission

MRS Proceedings ◽

10.1557/proc-524-197 ◽

1998 ◽

Vol 524 ◽

Author(s):

S. R. Mishra ◽

T. R. Cummins ◽

W. J. Gammon ◽

G. D. Waddill ◽

G. Van der-Laan ◽

...

Keyword(s):

Angular Distribution ◽

Cross Section ◽

Photon Energy ◽

Photoelectron Spectroscopy ◽

Emission Cross Section ◽

Linear Dichroism ◽

Constructive Interference ◽

Resonant Photoemission ◽

Magnetic Linear Dichroism ◽

Spectroscopy Experiment

ABSTRACTThe constructive interference between direct and indirect channels above the absorption threshold of a core level leads to a massive increase in the emission cross section leading to a phenomenon called “resonant photoemission”. Using novel magnetic linear dichroism in angular distribution photoelectron spectroscopy experiment we have tried to understand the nature of the resonant photoemission process in Gd metal. The presence of dichroism in Gd 4f photoemission intensity at a photon energy corresponding to resonant photoemission clearly demonstrates the photoemission-like nature of the resonant photoemission process.

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X-ray photoelectron angular distributions with dispersion-compensating x-ray and electron optics

Journal of Electron Spectroscopy and Related Phenomena ◽

10.1016/0368-2048(77)85047-0 ◽

1977 ◽

Vol 11 (1) ◽

pp. 39-65 ◽

Cited By ~ 26

Author(s):

R.J. Baird ◽

C.S. Fadley

Keyword(s):

Angular Distributions ◽

Electron Optics ◽

X Ray ◽

Photoelectron Angular Distributions

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Single antiferromagnetic axis of Fe in orthorhombic YMn0.5Fe0.5O3 films observed by x-ray magnetic linear dichroism

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.11.226 ◽

2019 ◽

Vol 780 ◽

pp. 79-84

Author(s):

Shu Chih Haw ◽

Chang Yang Kuo ◽

Zhiwei Hu ◽

Je Wei Lin ◽

Jenn Min Lee ◽

...

Keyword(s):

Linear Dichroism ◽

X Ray ◽

Magnetic Linear Dichroism

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Magnetic x-ray linear dichroism in the photoelectron spectroscopy of ultrathin magnetic alloy films

Journal of Applied Physics ◽

10.1063/1.362262 ◽

1996 ◽

Vol 79 (8) ◽

pp. 5626 ◽

Cited By ~ 16

Author(s):

J. G. Tobin ◽

K. W. Goodman ◽

G. J. Mankey ◽

R. F. Willis ◽

J. D. Denlinger ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Linear Dichroism ◽

Magnetic Alloy ◽

Alloy Films ◽

X Ray

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EPITAXY OF ULTRATHIN CoO FILMS STUDIED BY XPD AND GIXRD

Surface Review and Letters ◽

10.1142/s0218625x0200324x ◽

2002 ◽

Vol 09 (02) ◽

pp. 937-941 ◽

Cited By ~ 6

Author(s):

P. LUCHES ◽

C. GIOVANARDI ◽

T. MOIA ◽

S. VALERI ◽

F. BRUNO ◽

...

Keyword(s):

Synchrotron Radiation ◽

Lattice Constant ◽

Photoelectron Spectroscopy ◽

Grazing Incidence ◽

X Ray Diffraction ◽

Direction Parallel ◽

X Ray ◽

Photoelectron Diffraction ◽

Rocksalt Structure ◽

Plane Lattice

CoO layers have been grown by exposing to oxygen the (001) body-centered-tetragonal (bct) surface of a Co ultrathin film epitaxially grown on Fe(001). Different oxide thicknesses in the 2–15 ML range have been investigated by means of synchrotron-radiation-based techniques. X-ray photoelectron spectroscopy has been used to check the formation of the oxide films; X ray photoelectron diffraction has given information concerning the symmetry of their unit cell; grazing incidence X-ray diffraction has allowed to evaluate precisely their in-plane lattice constant. The films show a CoO(001) rocksalt structure, rotated by 45° with respect to the bct Co substrate, with the [100] direction parallel to the substrate [110] direction. Their in-plane lattice constant increases as a function of thickness, to release the in-plane strain due to the 3% mismatch between the bulk CoO phase and the underlying substrate.

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