Ethylene photoelectron spectrum

Figure 10-7 Photoelectron Spectrum of Ethylene. Energies of the highest three eigenvalues, converted to eV, are shown below the spectmm.

A study of the valence band photoelectron spectrum and the X-ray emission spectrum of poly(ethylene oxide) was carried out by Brena and co-workers [102] in order to understand the effect of conformation on the observed spectra. Up to 12 monomers were used in the calculations for the valence band photoelectron... 

Further evidence is the x-ray photoelectron spectrum of the catalyst, which is about the same whether the reduction is carried out in CO or in ethylene (30). However, more positive evidence comes from Baker and Carrick (32) who measured the valence on a catalyst exposed to ethylene at 125°C, a typical polymerization temperature. Within a few minutes they obtained 85-96% conversion to Cr(II). Formaldehyde was the by-product. 

Interestingly, the energy of the HOMO of bicyclobutane was found to be higher than that of ethylene The first electronic transition in bicyclobutane, namely the n-n (HOMO-LUMO) transition, is lower in energy than in ethylene" The position of the onset of the first band in its photoelectron spectrum suggests an adiabatic ionization energy of 8.70... 

Figure 6. The UV photoelectron spectrum of ethylene. Baker et al. [25, 57], Reproduced by permission from Elsevier Science-NL...

Figure 2 Top photoelectron spectrum of ethylene. Bottom breakdown graph of ethylene determined by photoion-photoelectron coincidence measurements. Triangles and dots yields of C2H2" and C2H3 ions, respectively, obtained by collision experiments. The ground and excited electronic states of the C2H4 ion are denoted by X, A, B and C.

In most ionic unimolecular reactions, internal conversion to the ground electronic state is rapid compared to dissociation. In a few cases, however, evidence has been found of a rapid and specific dissociation process occurring on the potential energy surface of an excited electronic state. When such an isolated state decay occurs, a correlation exists between the branching ratio for the specific channel and the photoelectron spectrum. Ionized difluoro-ethylenes for example, dissociate statistically below the IC state but this latter state favours strongly the F loss channel. 

Fig. 9. The charge-exchange mass spectrum of ethylene as a function of energy/ together with its photoelectron spec-trum.< 2 ">...

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