Subject electron energy losses

Vibrations in molecules or in solid lattices are excited by the absorption of photons (infrared spectroscopy), or by the scattering of photons (Raman spectroscopy), electrons (electron energy loss spectroscopy EELS), or neutrons (inelastic neutron scattering). In case the vibration is excited by the interaction of the bond with a wave field - as with photons and electrons - the excitation is subject to strict selection rules. Collisions, on the other hand, excite all vibrational modes. 

Contents Introduction. - Volume Plasmons. - The Dielectric Function and the Loss Function of Bound Electrons. -Excitation of Volume Plasmons. - The Energy Loss Spectrum of Electrons and the Loss Function. - Experimental Results. - The Loss Width. - The Wave Vector Dependency of the Energy of the Volume Plasmon. - Core Excitations. -Application to Microanalysis. - Energy Losses by Excitation of Cerenkov Radiation and Guided Light Modes. - Surface Excitations. - Different Electron Energy Loss Spectrometers. - Notes Added in Proof - References. - Subject Index. 

Figure 15.33 (a) Electron energy loss spectra of MgO(OOl) thin films subjected to elec-... 

Radiation induced changes in the electronic structure of all samples were evident as changes in energy loss spectrum with increased exposure to the electron beam. The spectrum of radiation induced chromophores could thus be studied (1 ). Spectra recorded at the earliest exposure times compared favorably with optical results and are believed to contain primarily intrinsic electronic excitations (1, 2, 4). An analysis of these intrinsic spectra is the subject of the bulk of this paper. The spectra of radiation damaged polymers are described briefly after the intrinsic excitations are discussed. 

A mass spectral study of the 1,1-dihalogeno precursors of (10) and (11) and suitable deuteriated analogues has shown that complete hydrogen scrambling occurs prior to the loss of H or X from the molecular ion. A series of cyclopropyl ethers has been subjected to chemical ionization mass spectrometry and other routine electron-impact studies of cyclopropane-containing compounds are included for completeness. The gas-phase ion chemistry of monosubstituted cyclopropanes has been examined and ion-impact energy-loss spectrometry applied to a series of cycloalkenes including cyclopropene. ... 

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