scholarly journals Structure of X-ray photoelectron spectra of low-energy and core electrons of Ln(C6H4OCH3COO-)3

2005 ◽  
Vol 20 (2) ◽  
pp. 17-22
Author(s):  
Yury Teterin ◽  
Labud Vukcevic ◽  
Anton Teterin
Keyword(s):  
Fine Structure ◽  
Binding Energy ◽  
Electron Spectroscopy ◽  
Amorphous Materials ◽  
Chemical Properties ◽  
Dynamic Effect ◽  
Electronic Configuration ◽  
Photoelectron Spectra ◽  
Spectral Structure ◽  
X Ray

This paper deals with the results of an X-ray photo electron spectroscopy of lanthanide ortho-metoxybenzoates Ln(C6H4OCH3COO-)3, where Ln represents lanthanides La through Lu except for Pm and C6H4OCH3COO- - residuum of ortho-metoxybenzoic acid. The core and outer electron X-ray photo electron spectroscopy spectra in the binding energy range of 0-1250 eV were shown to exhibit a complex, fine structure. The said structure was established due to the outer (0-15 eV binding energy) and inner (15-50 eV binding energy) valence molecular orbital from the filled Ln5p and O2s atomic shells multiple splitting, many-body perturbation, dynamic effect, etc. The mechanisms of such a fine structure formation were shown to manifest different probabilities in the spectrum of a certain electronic shell. There fore, the fine X-ray photo electron spectroscopy spectral structure resulting from a certain mechanism can be interpreted and its quantitative parameters related to the physical and chemical properties of the studied com pounds (degree of delocalization and participation of Ln4f electrons in the chemical bond, electronic configuration and oxidation states, density of uncoupled electrons on paramagnetic ions, degree of participation of the low binding energy filled electronic shells of lanthanide and ligands information of the outer and in nervalence molecular orbitals, lanthanide close environment structure in amorphous materials, etc).

scholarly journals X-ray photoelectron spectra structure and chemical bonding in AmO2

2015 ◽  
Vol 30 (2) ◽  
pp. 83-98 ◽  
Author(s):  
Yury Teterin ◽  
Konstantin Maslakov ◽  
Mikhail Ryzhkov ◽  
Anton Teterin ◽  
Kirill Ivanov ◽  
...  
Keyword(s):  
Binding Energy ◽  
Energy Range ◽  
Chemical Bond ◽  
Theoretical Data ◽  
Molecular Orbitals ◽  
Binding Energies ◽  
Photoelectron Spectra ◽  
Spectral Structure ◽  
Discrete Variation ◽  
X Ray

Quantitative analysis was done of the X-ray photoelectron spectra structure in the binding energy range of 0 eV to ~35 eV for americium dioxide (AmO2) valence electrons. The binding energies and structure of the core electronic shells (~35 eV-1250 eV), as well as the relativistic discrete variation calculation results for the Am63O216 and AmO8 (D4h) cluster reflecting Am close environment in AmO2 were taken into account. The experimental data show that the many-body effects and the multiplet splitting contribute to the spectral structure much less than the effects of formation of the outer (0-~15 eV binding energy) and the inner (~15 eV-~35 eV binding energy) valence molecular orbitals. The filled Am 5f electronic states were shown to form in the AmO2 valence band. The Am 6p electrons participate in formation of both the inner and the outer valence molecular orbitals (bands). The filled Am 6p3/2 and the O 2s electronic shells were found to make the largest contributions to the formation of the inner valence molecular orbitals. Contributions of electrons from different molecular orbitals to the chemical bond in the AmO8 cluster were evaluated. Composition and sequence order of molecular orbitals in the binding energy range 0-~35 eV in AmO2 were established. The experimental and theoretical data allowed a quantitative scheme of molecular orbitals for AmO2, which is fundamental for both understanding the chemical bond nature in americium dioxide and the interpretation of other X-ray spectra of AmO2.

scholarly journals Valence XPS structure and chemical bond in Cs2UO2Cl4

2016 ◽  
Vol 31 (1) ◽  
pp. 37-50 ◽  
Author(s):  
Yury Teterin ◽  
Konstantin Maslakov ◽  
Mikhail Ryzhkov ◽  
Anton Teterin ◽  
Kirill Ivanov ◽  
...  
Keyword(s):  
Binding Energy ◽  
Chemical Bond ◽  
Theoretical Data ◽  
Molecular Orbitals ◽  
Photoelectron Spectra ◽  
Spectral Structure ◽  
Many Body ◽  
Discrete Variation ◽  
X Ray ◽  
Calculation Results

Quantitative analysis was done of the valence electrons X-ray photoelectron spectra structure in the binding energy (BE) range of 0 eV to ~35 eV for crystalline dicaesium tetrachloro-dioxouranium (VI) (Cs2UO2Cl4). This compound contains the uranyl group UO2. The BE and structure of the core electronic shells (~35 eV-1250 eV), as well as the relativistic discrete variation calculation results for the UO2Cl4(D4h) cluster reflecting U close environment in Cs2UO2Cl4 were taken into account. The experimental data show that many-body effects due to the presence of cesium and chlorine contribute to the outer valence (0-~15 eV BE) spectral structure much less than to the inner valence (~15 eV-~35 eV BE) one. The filled U5f electronic states were theoretically calculated and experimentally confirmed to be present in the valence band of Cs2UO2Cl4. It corroborates the suggestion on the direct participation of the U5f electrons in the chemical bond. Electrons of the U6p atomic orbitals participate in formation of both the inner (IVMO) and the outer (OVMO) valence molecular orbitals (bands). The filled U6p and the O2s, Cl3s electronic shells were found to make the largest contributions to the IVMO formation. The molecular orbitals composition and the sequence order in the binding energy range 0 eV-~35 eV in the UO2Cl4 cluster were established. The experimental and theoretical data allowed a quantitative molecular orbitals scheme for the UO2Cl4 cluster in the BE range 0-~35 eV, which is fundamental for both understanding the chemical bond nature in Cs2UO2Cl4 and the interpretation of other X-ray spectra of Cs2UO2Cl4. The contributions to the chemical binding for the UO2Cl4 cluster were evaluated to be: the OVMO contribution - 76%, and the IVMO contribution - 24 %.

scholarly journals PHYSICAL AND CHEMICAL STUDIES OF OVERROOF ROCKS OF CLAY SHALES OF THE DZHERDANAK DEPOSIT

2021 ◽  
pp. 16-21
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Chemical Properties ◽  
Mineralogical Composition ◽  
Physical And Chemical Properties ◽  
X Ray ◽  
Clay Shales ◽  
Chemical Studies ◽  
Physical And Chemical ◽  
And Chemical Properties

The purpose of this study is study of the physical and chemical properties of the overburden of the Dzherdanak deposit. The chemical and mineralogical composition of the overburden of the Djerdanak deposit has been studied by the methods of X-ray and thermography, electron microscopy and infrared spectroscopy. The main phases are quartz, kaolinite and muscovite. The study of the fine structure of the rock under an electron microscope showed the homogeneity of the rock with pronounced uniform inclusions, which is preserved even after firing. Changes in the rock after firing at 1050 °C have been determined. The formation of mullite at this temperature has been established.

scholarly journals X-ray spectroscopy study of ThO2 and ThF4

2010 ◽  
Vol 25 (1) ◽  
pp. 8-12
Author(s):  
Anton Teterin ◽  
Mikhail Ryzhkov ◽  
Yury Teterin ◽  
Ernst Kurmaev ◽  
Konstantin Maslakov ◽  
...  
Keyword(s):  
Binding Energy ◽  
Energy Range ◽  
Density Distribution ◽  
Electronic State ◽  
Electronic States ◽  
State Density ◽  
Molecular Orbitals ◽  
Spectral Structure ◽  
X Ray ◽  
Electronic State Density

The structure of the X-ray photoelectron, X-ray O(F)Ka-emission spectra from ThO2 and ThF4 as well as the Auger OKLL spectra from ThO2 was studied. The spectral structure was analyzed by using fully relativistic cluster discrete variational calculations of the electronic structure of the ThO8 D4h) and ThF8 (C2) clusters reflecting thorium close environment in solid ThO2 and ThF4. As a result it was theoretically found and experimentally confirmed that during the chemical bond formation the filled O(F)2p electronic states are distributed mainly in the binding energy range of the outer valence molecular orbitals from 0-13 eV, while the filled O(F)2s electronic states - in the binding energy range of the inner valence molecular orbitals from 13-35 eV. It was shown that the Auger OKLL spectral structure from ThO2 characterizes not only the O2p electronic state density distribution, but also the O2s electronic state density distribution. It agrees with the suggestion that O2s electrons participate in formation of the inner valence molecular orbitals, in the binding energy range of 13-35 eV. The relative Auger OKL2-3L2-3 peak intensity was shown to reflect quantitatively the O2p electronic state density of the oxygen ion in ThO2.

scholarly journals Axial Coordination of Phosphine or Phosphite to Iron(III) Chlorophyll a

1995 ◽  
Vol 50 (8) ◽  
pp. 1222-1228 ◽  
Author(s):  
Hidenari Inoue ◽  
Hiromi Akahori ◽  
Yuri Ohno ◽  
Katsuo Nakazawa ◽  
Yoshimune Nonomura ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
Iron Atom ◽  
Free Ligand ◽  
Electronic Configuration ◽  
Photoelectron Spectra ◽  
Field Range ◽  
Nmr Spectrum ◽  
X Ray ◽  
Axial Coordination ◽  
H Nmr

The adduct formation of iron(III) chlorophyll a with phosphines or phosphites has been studied by spectroscopic methods. The red-shift in the Soret and Q bands caused by the axial coordination of phosphine or phosphite to iron(III) chlorophyll a is an evidence for the autoreduction of the central iron(III) ion. The 31P{1H} NMR spectrum of bis-adducts measured in the presence of excess phosphine or phosphite ligands gave a single peak in the down field range compared to that of the corresponding free ligand. The ESR and X-ray photoelectron spectra have revealed that the central iron atom of the bis-adduct of iron chlorophyll a with phosphines or phosphites is divalent and in the low-spin state. The axial coordination of phosphine or phosphite influences the electronic configuration of the central iron atom and the macrocyclic chlorine ligand to induce the autoreduction of the central iron(III) ion.

Extended X-ray absorption fine-structure analysis of vacuum-deposited amorphous germanium

1989 ◽  
Vol 67 (4) ◽  
pp. 358-364 ◽  
Author(s):  
G. W. Johnson ◽  
D. E. Brodie ◽  
E. D. Crozier
Keyword(s):  
Fine Structure ◽  
Amorphous Materials ◽  
Amorphous Material ◽  
Amorphous Structure ◽  
Low Energy ◽  
X Ray Diffraction ◽  
Two Phase ◽  
Edge Structure ◽  
X Ray ◽  
Low Energy Electrons

In this study, thin films of germanium have been vacuum deposited in four regimes. Care was taken to prepare reproducible films, which required that the partial pressure of water be below 10−8 Torr during deposition (1 Torr = 133.3 Pa). First, films deposited onto substrates held during deposition at a temperature Ts that is below 473 K are amorphous. Once annealed above 423 K, their electrical conductivity and optical band gap are independent of deposition temperature and rate, and of whether or not low-energy electron irradiation of the substrate is used during deposition. This suggests that a well-defined and reproducible structure is being prepared. Second, a "precrystallization regime" is obtained when Ts is between 473 and 513 K. Extended X-ray adsorption fine-structure and X-ray diffraction confirm that this regime is a two-phase mixture of amorphous material and crystallites. Third, films deposited with Ts near 513 K, while using low-energy electrons to bombard the substrate, are amorphous, but these films have different electrical and optical properties from the films m the first regime. From this, we infer that a second well-defined amorphous structure exists. Fourth, films deposited with Ts above 513 K are polycrystalline. Extended X-ray adsorption fine-structure and X-ray adsorption near-edge structure could not distinguish between the two amorphous materials in the first and third regimes.

Electron Spectroscopic Studies of the Oxidation of Ni/Pd Alloys

1976 ◽  
Vol 31 (2) ◽  
pp. 205-210 ◽  
Author(s):  
K. Wandelt ◽  
G. Ertl
Keyword(s):  
Binding Energy ◽  
Auger Electron Spectroscopy ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Spectroscopic Studies ◽  
Oxide Layers ◽  
X Ray ◽  
Appearance Potential

Abstract The oxidation of polycrystalline samples of Ni/Pd-alloys at 600 °C and 2·10-5 Torr O2 has been investigated by means of Auger electron spectroscopy and soft x-ray appearance potential spectroscopy. The clean surfaces are enriched by Pd; and with increasing Pd content the binding energy of the Ni 2p-core levels was found to decrease continuously by 0.7 eV. After completion of the oxidation identical overlayers were formed on all samples (except on pure Pd!) which were identified to consist of NiO. Within the depth probed by the applied techniques (≲20 Å) the rate of oxidation was found to increase with increasing Pd content, which is in contrast to the behaviour to be expected for the growth of thick oxide layers after the formation of a coherent NiO overlayer.

scholarly journals Biogenic Formation of As-S Nanotubes by Diverse Shewanella Strains

2009 ◽  
Vol 75 (21) ◽  
pp. 6896-6899 ◽  
Author(s):  
Shenghua Jiang ◽  
Ji-Hoon Lee ◽  
Min-Gyu Kim ◽  
Nosang V. Myung ◽  
James K. Fredrickson ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Reduction Rate ◽  
Shewanella Oneidensis ◽  
Chemical Properties ◽  
Anaerobic Conditions ◽  
X Ray ◽  
Shewanella Alga ◽  
X Ray Absorption ◽  
And Chemical Properties

ABSTRACT Shewanella sp. strain HN-41 was previously shown to produce novel, photoactive, As-S nanotubes via the reduction of As(V) and S2O3 2− under anaerobic conditions. To determine if this ability was unique to this bacterium, 10 different Shewanella strains, including Shewanella sp. strain HN-41, Shewanella sp. strain PV-4, Shewanella alga BrY, Shewanella amazonensis SB2B, Shewanella denitrificans OS217, Shewanella oneidensis MR-1, Shewanella putrefaciens CN-32, S. putrefaciens IR-1, S. putrefaciens SP200, and S. putrefaciens W3-6-1, were examined for production of As-S nanotubes under standardized conditions. Of the 10 strains examined, three formed As-S nanotubes like those of strain HN-41. While Shewanella sp. strain HN-41 and S. putrefaciens CN-32 rapidly formed As-S precipitates in 7 days, strains S. alga BrY and S. oneidensis MR-1 reduced As(V) at a much lower rate and formed yellow As-S after 30 days. Electron microscopy, energy-dispersive X-ray spectroscopy, and extended X-ray absorption fine-structure spectroscopy analyses showed that the morphological and chemical properties of As-S formed by strains S. putrefaciens CN-32, S. alga BrY, and S. oneidensis MR-1 were similar to those previously determined for Shewanella sp. strain HN-41 As-S nanotubes. These studies indicated that the formation of As-S nanotubes is widespread among Shewanella strains and is closely related to bacterial growth and the reduction rate of As(V) and thiosulfate.

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