Evolution of diffusion coefficient of photoexcited species in excimer forming organic thin films

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389013%3A_____%2F20%3A00519233" target="_blank" >RIV/61389013:_____/20:00519233 - isvavai.cz</a>

Výsledek na webu

<a href="https://pubs.acs.org/doi/abs/10.1021/acs.jpcc.9b08953" target="_blank" >https://pubs.acs.org/doi/abs/10.1021/acs.jpcc.9b08953</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.jpcc.9b08953" target="_blank" >10.1021/acs.jpcc.9b08953</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Evolution of diffusion coefficient of photoexcited species in excimer forming organic thin films

Popis výsledku v původním jazyce

The diffusion of photogenerated excitons in organic semiconductors represents often a rate-determining process in the exciton population evolution in ultrafast transient absorption experiments, due to an increased mutual exciton interaction probability at typical excitation densities. A simple description of a diffusion process with a time-independent diffusion coefficient often fails to explain the observed kinetics in the highly nonequilibrium system. In this work, we used the concept of time-dependent diffusion and determined the evolution of the diffusion coefficient of photogenerated excited species in thin films of bis(terpyridine-4′-yl)terthiophene from the experimental ultrafast transient absorption spectroscopic data at a subnanosecond time scale. We show that the diffusion coefficient decreases in time more rapidly with increasing intensity of the photoexcitation. We explain the dependences by the planarization of photoexcited molecules and excimer formation.

Název v anglickém jazyce

Evolution of diffusion coefficient of photoexcited species in excimer forming organic thin films

Popis výsledku anglicky

The diffusion of photogenerated excitons in organic semiconductors represents often a rate-determining process in the exciton population evolution in ultrafast transient absorption experiments, due to an increased mutual exciton interaction probability at typical excitation densities. A simple description of a diffusion process with a time-independent diffusion coefficient often fails to explain the observed kinetics in the highly nonequilibrium system. In this work, we used the concept of time-dependent diffusion and determined the evolution of the diffusion coefficient of photogenerated excited species in thin films of bis(terpyridine-4′-yl)terthiophene from the experimental ultrafast transient absorption spectroscopic data at a subnanosecond time scale. We show that the diffusion coefficient decreases in time more rapidly with increasing intensity of the photoexcitation. We explain the dependences by the planarization of photoexcited molecules and excimer formation.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10404 - Polymer science

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Physical Chemistry C

ISSN

1932-7447

e-ISSN

—

Svazek periodika

124

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

8

Strana od-do

52-59

Kód UT WoS článku

000507149600008

EID výsledku v databázi Scopus

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