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Electron affinities distribution

By introducing reasonable values (about 2 for nitrogen, 4 for oxygen) for the electron affinity parameter relative to carbon, 8, and for the induced electron affinity for adjacent atoms (32/8i = Vio), we have shown that the calculated permanent charge distributions for pyridine, toluene, phenyltrimethylammonium ion, nitrobenzene, benzoic acid, benzaldehyde, acetophenone, benzo-nitrile, furan, thiophene, pyrrole, aniline, and phenol can be satisfactorily correlated qualitatively with the observed positions and rates of substitution. For naphthalene and the halogen benzenes this calculation does not lead to results... [Pg.201]

The initiator efficiency has to be considered jointly with the monomers involved The nucleophilicity of the initiator should be matched to the electron affinity of the monomer, as initiation should be fast and quantitative 7). If it is too small, initiation may be slow (and/or incomplete), which implies broadening of the molecular weight distribution and possibly loss of molecular weight control. If the nucleophilicity of the initiator is too high, side reactions may occur, as in the case of methyl methacrylate, where the ester carbonyl is attacked15). [Pg.150]

The electron affinity of the metal surface is high in relation to that of the foreign adsorbed molecule whose electron shell is easily displaced (for example with hydrogen atoms or in the presence of r electrons) or asymmetrically distributed (if the... [Pg.305]

Because of its lower electron affinity, Te sites trap holes which can then coulombically bind an electron in or near the conduction band to form an exciton. Subsequent radiative collapse of this exciton leads to emission (10,11,12,13). In the context of the PEC, emission thus serves as a probe of electron-hole (e -h" ) pair recombination which competes with e - h+ pair separation leading to photocurrent. Except for intensity, the emitted spectral distribution is found to be independent of the presence and/or composition of polychalcogenide electrolyte, excitation wavelength (Ar ion laser lines, 457.9-514.5 nm) and intensity (<30 mW/cnZ), and applied potential (-0.3V vs. SCE to open circuit) (6,1,8,9). [Pg.295]

Electron photodetachment spectra for indenyl and fluorenyl anions have been measured and the electron affinities of the corresponding radical and bond dissociation energies of the corresponding neutrals determined. Comparison has been made with solution-phase data in an attempt to determine the dependence of gas and solution properties on ionic size and extent of charge distribution.3 Benzocyclopropenyl anion... [Pg.327]


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See also in sourсe #XX -- [ Pg.3 , Pg.4 , Pg.1730 , Pg.1731 , Pg.2519 ]




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Affinity distribution

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Electron distribution

Electronic affinity

Electronic distribution

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