Polarization Resolved Optical Excitation of Charge-Transfer Excitons in PEN:PFP Cocrystalline Films: Limits of Nonperiodic Modeling

AbstractWhen a three-dimensional material is constructed by stacking different two-dimensional layers into an ordered structure, new and unique physical properties can emerge. An example is the delafossite PdCoO2, which consists of alternating layers of metallic Pd and Mott-insulating CoO2 sheets. To understand the nature of the electronic coupling between the layers that gives rise to the unique properties of PdCoO2, we revealed its layer-resolved electronic structure combining standing-wave X-ray photoemission spectroscopy and ab initio many-body calculations. Experimentally, we have decomposed the measured VB spectrum into contributions from Pd and CoO2 layers. Computationally, we find that many-body interactions in Pd and CoO2 layers are highly different. Holes in the CoO2 layer interact strongly with charge-transfer excitons in the same layer, whereas holes in the Pd layer couple to plasmons in the Pd layer. Interestingly, we find that holes in states hybridized across both layers couple to both types of excitations (charge-transfer excitons or plasmons), with the intensity of photoemission satellites being proportional to the projection of the state onto a given layer. This establishes satellites as a sensitive probe for inter-layer hybridization. These findings pave the way towards a better understanding of complex many-electron interactions in layered quantum materials.

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Reflection and absorption spectra of singlet charge transfer excitons in anthracene–PMDA crystals

The Journal of Chemical Physics ◽

10.1063/1.439681 ◽

1980 ◽

Vol 72 (7) ◽

pp. 4019-4030 ◽

Cited By ~ 50

Author(s):

Aldo Brillante ◽

Michael R. Philpott

Keyword(s):

Charge Transfer ◽

Absorption Spectra ◽

Charge Transfer Excitons

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Non-doped thermally activated delayed fluorescent organic light-emitting diodes using an intra- and intermolecular exciplex system with a meta-linked acridine–triazine conjugate

Journal of Materials Chemistry C ◽

10.1039/c8tc02590h ◽

2018 ◽

Vol 6 (34) ◽

pp. 9049-9054 ◽

Cited By ~ 7

Author(s):

Seongjin Jeong ◽

Youngnam Lee ◽

Joon Ki Kim ◽

Du-Jeon Jang ◽

Jong-In Hong

Keyword(s):

Charge Transfer ◽

Light Emitting Diodes ◽

Organic Light Emitting Diodes ◽

Light Emitting ◽

Thermally Activated ◽

Highly Efficient ◽

Organic Light ◽

Intermolecular Charge Transfer ◽

Charge Transfer Excitons

We report new TADF molecules (AmT and AmmT) for highly efficient non-doped OLEDs utilizing intra- and intermolecular charge transfer excitons.

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Phonon-assisted Interfacial Charge Transfer Excitons in Graphene/h-BN van der Waals Heterostructures

Chinese Journal of Physics ◽

10.1016/j.cjph.2021.12.030 ◽

2021 ◽

Author(s):

Rui Yang ◽

Mengtao Sun

Keyword(s):

Charge Transfer ◽

Van Der Waals ◽

Van Der Waals Heterostructures ◽

Interfacial Charge Transfer ◽

Charge Transfer Excitons ◽

Interfacial Charge

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Quantum Dynamics of Exciton Transport and Dissociation in Multichromophoric Systems

Annual Review of Physical Chemistry ◽

10.1146/annurev-physchem-090419-040306 ◽

2021 ◽

Vol 72 (1) ◽

pp. 591-616 ◽

Cited By ~ 1

Author(s):

Wjatscheslaw Popp ◽

Dominik Brey ◽

Robert Binder ◽

Irene Burghardt

Keyword(s):

Charge Transfer ◽

Quantum Dynamics ◽

Low Frequency ◽

Functional Materials ◽

Phonon Modes ◽

Quantum Dynamical ◽

Exciton Migration ◽

Exciton Transport ◽

Charge Transfer Excitons ◽

Vibronic Couplings

Due to the subtle interplay of site-to-site electronic couplings, exciton delocalization, nonadiabatic effects, and vibronic couplings, quantum dynamical studies are needed to elucidate the details of ultrafast photoinduced energy and charge transfer events in organic multichromophoric systems. In this vein, we review an approach that combines first-principles parameterized lattice Hamiltonians with accurate quantum dynamical simulations using advanced multiconfigurational methods. Focusing on the elementary transfer steps in organic functional materials, we address coherent exciton migration and creation of charge transfer excitons in homopolymers, notably representative of the poly(3-hexylthiophene) material, as well as exciton dissociation at polymer:fullerene heterojunctions. We emphasize the role of coherent transfer, trapping effects due to high-frequency phonon modes, and thermal activation due to low-frequency soft modes that drive a diffusive dynamics.

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