Electron energy loss spectra EELS

The electron energy loss spectra (EEL) in Figure 3 shows the IR vibrational difference of cis and tram alkenes up to 170 K, arising from different geometry of the two a bonds between the metal and the double bond. At 300 K this difference is erased and both form C4H6, by loss of hydrogen11. The bond formed by the diene (1,3-butadiene) is shown to have the same vibrational properties. Hence, the authors conclude that the end product adsorbed is ... 

The impact scattering or sudden mechanism has been used to explain the vibrational excitation of chemisorbed molecules in electron energy loss spectra (EELS). See in particular the reference by Tong et al. [25]. 

The advantage of this expression is that U and J appear only as their difference (U-J) and so it requires only a single parameter to be determined for any particular transihon metal oxide under considerahon. The J parameter shows little system-to-system variabihty and is taken to be around 1 eV in most cases. Based on a comparison of the calculated DOS and experimental electron energy loss spectra (EELS) the U parameter for NiO was set at 6.2 eV. This gave a ground state in which the Ni spins are aligned within (111) planes and neighboring planes have... 

Figure 5.20 Electron energy loss spectra (EELS) of detonation diamond (a) low-loss region, (b) core-loss region ( Taylor Francis 1997).

Transmission electron energy loss spectra (EELS) were obtained along the line A-B in Figure 3. The spectra were measured with 300 kV incident electrons and the single inelastic scattering distribution was obtained (11, 12). The spectra from the polyamide matrix and subinclusion were found to be very similar, indicating that the domain consists of nylon subinclusions within EPR rather than of two different mixed miscible phases of different composition (13). 

In Pfluger, Fink, Weber and Bohnen (1984) the optical properties of TiC and VC (and of TiN and VN) have been studied making use of electronic energy loss spectra (EELS) and have been compared with the interband DOS determined from band calculations. The EELS is a function of the volume energy losses Im( — 1/e), from which the real part 1/e can be found by making use of the Kramers-Kronig transformation. The imaginary part Sj is related to the optical DOS Ii(E) as follows ... 

Electron energy-loss spectra (EELS) were obtained by means of a Kesmodel EELS spectrometer (Bloomington, Indiana 47405, U.S.A.). Beam current at the sample was approximately 100 pA beam energy was 4 eV. The spectrometer produced a resolution of about 10 meV F.W.H.M. (80 cm ) in these experiments. 

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