Concerning the stability of biexcitons in hybrid HJ aggregates of π-conjugated polymers

Frenkel excitons are the primary photoexcitations in organic semiconductors and are ultimately responsible for the optical properties of such materials. They are also predicted to form bound exciton pairs, termed biexcitons, which are consequential intermediates in a wide range of photophysical proc...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of chemical physics 2022-05, Vol.156 (18), p.181101-181101
Main Authors: Bittner, Eric R., Silva, Carlos
Format: Article
Language:English
Subjects:
Aggregates
Coherence
Dipoles
Excitons
Optical properties
Organic semiconductors
Physics
Quantum phenomena
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Frenkel excitons are the primary photoexcitations in organic semiconductors and are ultimately responsible for the optical properties of such materials. They are also predicted to form bound exciton pairs, termed biexcitons, which are consequential intermediates in a wide range of photophysical processes. Generally, we think of bound states as arising from an attractive interaction. However, here, we report on our recent theoretical analysis, predicting the formation of stable biexciton states in a conjugated polymer material arising from both attractive and repulsive interactions. We show that in J-aggregate systems, 2J-biexcitons can arise from repulsive dipolar interactions with energies E2J > 2EJ, while in H-aggregates, 2H-biexciton states with energies E2H < 2EH can arise corresponding to attractive dipole exciton/exciton interactions. These predictions are corroborated by using ultrafast double-quantum coherence spectroscopy on a [poly(2,5-bis(3-hexadecylthiophene-2-yl)thieno[3,2-b]thiophene)] material that exhibits both J- and H-like excitonic behavior.
ISSN:0021-9606
1089-7690
DOI:10.1063/5.0090515