Polymers polarons

Neutral Polymer Polaron Bipolaron Bipolaron Bands... 

Neutral polymer Polaron Bipolaron Bipolaron bands... 

J. L. Bredas, R. R. Chance, R. Silbey, Comparative theoretical study of the doping of conjugated polymers - polarons in polyacetylene and polypara-phenylene, Physical Review B 1982, 26, 5843. 

Figure 3.6 Scheme of energy level of negative an extra electron, (c) Bipolaron state formed polaron and bipolaron in conjugated polymers upon the addition of a second electron, which after full relaxation of the polymer structure (the corresponds to the combination of two self-localized states), (a) A neutral polymer. polarons. 

Type 1, II, III Metal > - Polymer Polaron/bipolarons on polymer... 

Type 1 Metal Polymer Polaron/bipolarons on polymer and outer-sphere ET between metals... 

Anions Solvent molecules Charged polymer (polarons)... 

For spin-1/2 excitations such as electrons and holes in normal semiconductors or polarons in conjugated polymers, a single resonance is found centered at the Field... 

We have studied the temporal dynamics of CPG in m-LPPP by performing field-assisted pump-probe experiments on LED structures, as described in Section 8.3.2. The narrow line-width PA assigned to polarons (see Section 8.5.2) is a fingerprint of charge generation in m-LPPP. Monitoring the dynamics of these PA band enables us, for the first time, to directly observe the CPG dynamics in a conjugated polymer with sub-picosecond time resolution [40],... 

In molecular doped polymers the variance of the disorder potential that follows from a plot of In p versus T 2 is typically 0.1 eV, comprising contributions from the interaction of a charge carrier with induced as well as with permanent dipoles [64-66]. In molecules that suffer a major structural relaxation after removal or addition of an electron, the polaron contribution to the activation energy has to be taken into account in addition to the (temperature-dependent) disorder effect. In the weak-field limit it gives rise to an extra Boltzmann factor in the expression for p(T). More generally, Marcus-type rates may have to be invoked for the elementary jump process [67]. 

The polaron is characterized by the reversal of bond alternation, which, in the case of polythiophene, extends over five monomer units [30-32], and the appearance of two localized stales in the band gap ). These states have been indeed observed by UV-V1S absorption of both oligomers and polymers, in solution [33— 40] and in the solid state [41-45]. 

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