Universal exciton size in organic polymers is determined by nonlocal orbital exchange in time-dependent density functional theory

• Verfasst von: Mewes, Stefanie [VerfasserIn]
• Verfasst von: Plasser, Felix [VerfasserIn]
• Verfasst von: Dreuw, Andreas [VerfasserIn]
• Titel: Universal exciton size in organic polymers is determined by nonlocal orbital exchange in time-dependent density functional theory
• Verf.angabe: Stefanie A. Mewes, Felix Plasser, and Andreas Dreuw
• Umfang: 6 S.
• Fussnoten: Gesehen am 30.11.2017
• Titel Quelle: Enthalten in: The journal of physical chemistry letters
• Jahr Quelle: 2017
• Band/Heft Quelle: 8(2017), 6, S. 1205-1210
• ISSN Quelle: 1948-7185
• DOI: doi:10.1021/acs.jpclett.7b00157
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1565889266

Abstract

The exciton size of the lowest singlet excited state in a diverse set of organic π-conjugated polymers is studied and found to be a universal, system-independent quantity of approximately 7 Å in the single-chain picture. With time-dependent density functional theory (TDDFT), its value as well as the overall description of the exciton is almost exclusively governed by the amount of nonlocal orbital exchange. This is traced back to the lack of the Coulomb attraction between the electron and hole quasiparticles in pure TDDFT, which is reintroduced only with the admixture of nonlocal orbital exchange.