Study of average valence and valence electron distribution of several oxides using X-ray photoelectron spectra

Deformation and valence-electron densities in silicon are derived via Fourier summation and multipole refinement of highly accurate measurements of X-ray structure factors. These results provide a new perspective for the comparison between theory and experiment. The model electron density derived from experiment is in quantitative agreement with recent solid-state calculations, but not with earlier experimental results reported by Yang & Coppens [Solid State Commun. (1974), 15, 1555-1559].

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Is a Shake up Process Responsible for the Multi-peak Structure of the X-ray Photoelectron Spectra of Metal Hexacarbonyls?

Zeitschrift für Naturforschung A ◽

10.1515/zna-1972-0517 ◽

1972 ◽

Vol 27 (5) ◽

pp. 816-818

Author(s):

S Pignataro

Keyword(s):

Binding Energy ◽

Valence Electron ◽

Photoelectron Spectra ◽

Energy Spectra ◽

Excitation Process ◽

X Ray ◽

Simultaneous Excitation ◽

Peak Structure ◽

Metal Hexacarbonyls ◽

Binding Energy Region

AbstractThe X-ray photoelectron energy spectra of chromium, molybdenum and tungsten hexacarbonyls are found to show a multi-peak structure. This is particularly remarkable in the C1S and O1S binding energy region. This peculiarity is tentatively interpreted on the basis of a double excitation process involving the ionization and simultaneous excitation of a valence electron

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X-Ray Photoelectron Spectra of Valence Electron in (CuxNi1-x)S2 and ZnS2

Journal of the Physical Society of Japan ◽

10.1143/jpsj.43.1095 ◽

1977 ◽

Vol 43 (3) ◽

pp. 1095-1096 ◽

Cited By ~ 8

Author(s):

Hisao Yamamoto ◽

Takayuki Nakagawa ◽

Hideya Onodera ◽

Hiroshi Watanabe

Keyword(s):

Valence Electron ◽

Photoelectron Spectra ◽

X Ray

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Charge density study of N-acetyl-L-tyrosine ethyl ester monohydrate derived from CCD area detector data

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768198012099 ◽

1999 ◽

Vol 55 (2) ◽

pp. 226-230 ◽

Cited By ~ 12

Author(s):

S. Dahaoui ◽

C. Jelsch ◽

J. A. K. Howard ◽

C. Lecomte

Keyword(s):

Charge Density ◽

Ethyl Ester ◽

Electron Distribution ◽

Valence Electron ◽

X Ray Diffraction ◽

X Ray ◽

Area Detector ◽

Unique Data ◽

Thermal Vibrations ◽

Density Study

The crystal structure, thermal vibrations and electron density of the peptide N-acetyl-L-tyrosine ethyl ester monohydrate, C13H17NO4.H2O, have been analysed using single-crystal X-ray diffraction data collected at 110 K with Mo Kα radiation to a resolution of (\sin\theta/\lambda)_\max = 1.1 Å−1. A CCD area detector was used to collect 98 393 data during one week. A multipolar atom density model was fitted against the 10 189 unique data with I > 2σ(I) [R(F) = 0.027, wR(F) = 0.020, g.o.f. = 0.65] in order to map the valence electron distribution. These deformation densities compare very well with those obtained from conventional diffractometers equipped with scintillation detectors. This work shows that area detectors permit charge density studies in a more routine way than is possible with conventional diffractometers.

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Chemical Species Identification in an SEM by Changes in Emitted X-Ray Energies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052869 ◽

1974 ◽

Vol 32 ◽

pp. 570-571

Author(s):

R. H. Duff

Keyword(s):

Species Identification ◽

Valence Electron ◽

Chemical Species ◽

X Rays ◽

Chemical Bonds ◽

Small Shift ◽

X Ray ◽

Electron Transitions ◽

Peak Energy ◽

Chemical Combination

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.

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