Electron affinity, conjugated

I. D. W. Samuel, G. Rumbles, and C. J. Collison, Efficient inter-chain photoluminescence in a high electron affinity conjugated polymer, Phys. Rev. B 52 11573 (1995). 

Since the energy of the transfer band is determined by the difference between the donor ionization potential and the acceptor electron affinity, this fact points to the increase of the PCS ionization potential with decreasing conjugation efficiency. Therefore, the location of the transfer band of the molecular complexes of an acceptor and various PCSs can serve as a criterion for the conjugation efficiency in the latter. In Refs.267 - 272) the data for a number of molecular complexes are given, and the comparison with the electrical properties of the complexes is made. 

The electronic properties of these dyes can be tailored by changing the length of conjugation chain or by adding specific terminal groups Rj and R2. Due to their different electron affinities, these terminal groups can be classified into electron acceptor (A), and electron donor (D) groups. 

We saw previously that hydrated electrons react very rapidly with the conjugated 1,3-butadiene (k = 8 x 109 M-1 s 1). In less polar solvents the attachment of an electron to 1,3-butadiene (with adiabatic electron affinity of —0.62 eV20) will be slower. The... 

A new class of conjugated hydrocarbons is that of the fullerenes [11], which represent an allotropic modification of graphite. Their electrochemistry has been studied in great detail during the last decade [126]. The basic entity within this series is the Ceo molecule (23). Because of its high electron affinity, it can be reduced up to its hexaanion (Fig. 4) [14,127]. Solid-state measurements indicate that the radical anion of Ceo reversibly dimerizes. NMR measurements confirm a u-bond formation between two radical anion moieties [128,129]. 

Several effects can influence the electronic structure of Cjq upon metal complex formation. One is the removal of one double bond from the remaining 29 fullerene double bonds. As in any polyene system, this decreased conjugation is expected to raise the energy of the LUMO and therefore decreases the electron affinity of the system. Conversely, the d-orbital backbonding transfers electron density from the metal into n orbitals of the remaining double bonds, which also decreases the electron affinity. 

However, this loss of conjugation does not seem to affect the electron affinity of methanofullerenes. Numerous studies have shown that the redox potentials of methanofullerenes do not differ significantly from those of their fulleroid analogs [83], and until the year 2000,... 

The Br0nsted gas-phase acidity will be related to the proton affinity of the conjugate base. However, this gives us no estimate of the relative acidity of nonprotonk (Lewis) acids, (f the electron is the bask analogue of the acidk proton, then electron affinities should provide an inherent gas-phase measure of acidity that parallels proton affinities for bases.— That they have not been more frequently used in this connection is... 

Dewar and Rzepa found that the MNDO (Section 6.2.5.3) electron affinities of 26 molecules with delocalized HOMOs (mostly radicals and conjugated organic molecules) had an absolute mean error of 0.43 eV for ten molecules with the... 

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