The Characteristic Loss Spectra of the Second and Third Series Transition Metals

Characteristic electron energy loss spectra are presented for the second and third series transition metals Y, Zr, Nb, Mo, Rh, Pd, Ag, and Hf, Ta, W, Re, Ir, Pt, Au. An identification of most of the spectral features in terms of collective and individual particle excitations is made.

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Measurements of white line intensities in 4d transition metals using Electron Energy Loss Spectrometry (EELS)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153907 ◽

1989 ◽

Vol 47 ◽

pp. 386-387

Author(s):

Douglas H. Pearson

Keyword(s):

Transition Metals ◽

Energy Loss ◽

Electron Energy ◽

Background Intensity ◽

White Line ◽

Line Intensities ◽

Electron Energy Loss Spectrometry ◽

Electron Energy Loss ◽

Electron Energy Loss Spectra ◽

The Continuum

A feature of considerable interest in the electron energy loss spectra of transition metals is the L23 edge which is composed of two sharp “white lines” superimposed on a broad edge that makes up the trailing background. The white lines are due to the excitations of electrons from filled 2p1/2 and 2p3/2 states to unoccupied 3d or 4d states, and the background intensity is due to continuum excitations. Recent work on the white lines of the 3d transition metals has shown that when normalized to the continuum excitations, the total white line intensity decreases nearly linearly with atomic number (or d band occupancy) across the 3d series. Furthermore, this linear relationship may be used to measure the changes in 3d state occupancy local to specific atoms during alloying and during solid state phase transformations. In the present paper the experimental analysis of the white lines is extended to the 4d transition metals and is then compared to experimental results from the 3d metals.Electron-transparent specimens of the pure 4d metals were prepared by standard electropolishing and evaporation techniques. To prevent oxidation of the Yttrium specimen, however, a 40 nm film of Yttrium was deposited between 15 nm films of Vanadium by direct current ion sputtering in a chamber with a base pressure of < 1.0 × 10−7 Torr. Energy loss spectra were obtained using a Gatan 607 electron energy loss spectrometer attached to a Philips EM 430 electron microscope operating in image mode at 200 kV.

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Characteristic Electron Energy Loss Spectra of the Transition Metals, Ti to Cu

Proceedings of the Physical Society ◽

10.1088/0370-1328/76/6/306 ◽

1960 ◽

Vol 76 (6) ◽

pp. 857-869 ◽

Cited By ~ 110

Author(s):

J L Robins ◽

J B Swan

Keyword(s):

Transition Metals ◽

Energy Loss ◽

Electron Energy ◽

Electron Energy Loss ◽

Electron Energy Loss Spectra

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Parallel Detection of Electron Energy Loss Spectra in Direct Mode

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134004 ◽

1990 ◽

Vol 48 (2) ◽

pp. 82-83

Author(s):

Eckhard Quandt ◽

Stephan laBarré ◽

Andreas Hartmann ◽

Heinz Niedrig

Keyword(s):

Energy Loss ◽

Electron Energy ◽

Energy Resolution ◽

Large Angle ◽

Maximum Energy ◽

Semiconductor Detectors ◽

Parallel Detection ◽

Photodiode Arrays ◽

Electron Energy Loss ◽

Electron Energy Loss Spectra

Due to the development of semiconductor detectors with high spatial resolution -- e.g. charge coupled devices (CCDs) or photodiode arrays (PDAs) -- the parallel detection of electron energy loss spectra (EELS) has become an important alternative to serial registration. Using parallel detection for recording of energy spectroscopic large angle convergent beam patterns (LACBPs) special selected scattering vectors and small detection apertures lead to very low intensities. Therefore the very sensitive direct irradiation of a cooled linear PDA instead of the common combination of scintillator, fibre optic, and semiconductor has been investigated. In order to obtain a sufficient energy resolution the spectra are optionally magnified by a quadrupole-lens system.The detector used is a Hamamatsu S2304-512Q linear PDA with 512 diodes and removed quartz-glas window. The sensor size is 13 μm ∗ 2.5 mm with an element spacing of 25 μm. Along with the dispersion of 3.5 μm/eV at 40 keV the maximum energy resolution is limited to about 7 eV, so that a magnification system should be attached for experiments requiring a better resolution.

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