DIPC Community Seminars: Photophysics of organic materials from a computational perspective
DIPC Seminars
- Speaker
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Claire Tonnelé, Donostia International Physics Center
- When
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2022/06/09
14:00 - Place
- Hybrid Seminar, Donostia International Physics Center
- Add to calendar
-
iCal
**DIPC Community Seminars **
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In the past few decades, the field of organic electronics has received ever
increasing attention, taking organic semiconductors from fundamental research
to the hands of billions. However, despite tremendous efforts, the organic
light emitting diode (OLED) is the only application to have reached the
industrial market. Further improvement of organic materials for given
applications requires advanced understanding of their structure-property
relationships and underlying photophysical processes. In this talk, I will
give an overview of my work in this field from a computational perspective. In
particular, I will focus on two topics:
1\. Materials design for organic electronics requires to go beyond the
molecular properties and address the collective behavior of multiple units in
active layer thin films that depends on the supramolecular arrangement and
nature of intermolecular interactions. This complexity motivated the synthesis
and study of discrete multiunit assemblies of conjugated molecules with
controlled chemical/geometrical structures and restricted conformational
freedom. In a recent combined experimental and theoretical study, we have
demonstrated how chemical tuning of a newly synthesized cage architecture
allows precise control of the nature of the excited states, opening the way
for a rational design of well-defined multichromophoric assemblies.
2\. Neutral organic radical emitters are currently considered as a promising
new route for efficient OLEDs. Using conventional closed-shell materials,
electroluminescence efficiency of OLEDs is limited to 25%, as spin statistics
dictates that charge recombination leads to 25% singlets and 75% triplets, the
latter being intrinsically dark. While several strategies have been proposed
to brighten those triplets (inclusion of heavy metal atom, thermally activated
delayed fluorescence, etc), the use of radical emitters with spin-allowed
doublet emission is a conceptually superior solution to elegantly circumvent
the spin statistics limited efficiency issue. Very recently, we have described
what is so far the most investigated luminescent organic radical,TTM, and
showed how its photophysical properties can be tuned by substitution.
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