Singlet鈥揝inglet Exciton Recombination: Theoretical Insight into the Influence of High Density Regime of Excitons in Conjugated Polymers

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• 作者：Luiz Antonio Ribeiro Junior ; Wiliam Ferreira da Cunha ; Geraldo Magela e Silva
• 刊名：Journal of Physical Chemistry B
• 出版年：2014
• 出版时间：May 15, 2014
• 年：2014
• 卷：118
• 期：19
• 页码：5250-5257
• 全文大小：422K
• 年卷期：v.118,no.19(May 15, 2014)
• ISSN：1520-5207

文摘

Using a modified version of the Su鈥揝chrieffer鈥揌eeger (SSH) model combined with the extended Hubbard model (EHB), the recombination between a singlet exciton pair is investigated under the influence of an external electric field, electron鈥揺lectron interactions, and temperature effects in the scope of a nonadiabatic evolution method. The excitons are positioned very close to each other in a way to mimic a high-density region in monomolecular conjugated polymer systems. Results show that there are mainly three possible channels resulting from singlet鈥搒inglet exciton recombination: (1) forming an excited negative polaron and an excited positive bipolaron, (2) forming two free and excited oppositely charged polarons, and (3) forming a biexciton. These results suggest that the recombination processes critically depends on the condition imposed to the system. The description of this dependence, as carried out in the present work, may provide guidance to improve the generation of free charge carriers in organic optoelectronic devices.