Structural and solvent modulation of symmetry-breaking charge-transfer pathways in molecular triads DOI Creative Commons
Chinju Govind, Evangelos Balanikas, Gana Sanil

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Whereas the photoinduced charge-transfer properties of electron donor-acceptor dyads are now well understood, those symmetric conjugated architectures containing several identical branches have started to be scrutinised much more recently. Here, we report on our investigation dynamics a series formally centrosymmetric triads consisting quadrupolar dihydropyrrolopyrrole core substituted with two diphenylethynyl lateral branches. Using combination time-resolved electronic and vibrational spectroscopies, show that these molecules exhibit rich excited-state dynamics, which includes three different types symmetry-breaking processes depending nature end substituents as solvent: (i) symmetry breaking within core; (ii) charge transfer from one branches; (iii) between This illustrates how molecules, including location exciton, can controlled by fine tuning structural environmental parameters.

Language: Английский

Symmetry-Breaking Charge Separation Mediated Triplet Population in a Perylenediimide Trimer at the Single-Molecule Level DOI
Aniruddha Mazumder, Kavya Vinod, Philip Daniel Maret

et al.

The Journal of Physical Chemistry Letters, Journal Year: 2024, Volume and Issue: 15(22), P. 5896 - 5904

Published: May 28, 2024

Herein, we demonstrate triplet excited-state population in a conformationally rigid perylenediimide trimer (PDI-T) via intramolecular symmetry-breaking charge separation (SB-CS) at the single-molecule level. The fluorescence intensity trajectories of PDI-T nonpolar polystyrene matrix (ε = 2.60) exhibit prolonged with infrequent dark states, representing and/or transfer states. In contrast, poly(vinyl alcohol) 7.80), erratic blinking dynamics resulting low photon counts were observed, corroborating feasibility polar environment. agreement measurements, transient absorption spectroscopy reveals ultrafast SB-CS (τCS < 5 ps) tetrahydrofuran 7.58) and acetone 20.70), through recombination. current investigation shows utility weakly coupled molecular constructs controlling generation for potential applications optoelectronic devices.

Language: Английский

Citations

4
Guest-Mediated Modulation of Photophysical Pathways in a Coronene Bisimide Cyclophane DOI
Jessica Rühe, Kavya Vinod,

Hanna Hoh

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 12, 2024

The properties and functions of chromophores utilized by nature are strongly affected the environment formed protein structure in cells surrounding them. This concept is transferred here to host-guest complexes with encapsulated guests acting as an environmental stimulus. A new cyclophane host based on coronene bisimide presented that can encapsulate a wide variety planar guest molecules binding constants up (4.29 ± 0.32) × 10

Language: Английский

Citations

4
Unraveling the Origin of Multichannel Circularly Polarized Luminescence in a Pyrene‐Functionalized Topologically Chiral [2]Catenane DOI
Xueli Wang,

Peicong Wu,

Yu Wang

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: June 4, 2024

Mechanically interlocked molecules (MIMs) are promising platforms for developing functionalized artificial molecular machines. The construction of chiral MIMs with appealing circularly polarized luminescence (CPL) properties has boosted their potential application in biomedicine and the optical industry. However, there is currently little knowledge about CPL emission mechanism or dynamics these related MIMs. Herein, we demonstrate that time-resolved (TRCPL) spectroscopy combined transient absorption (TA) offers a feasible approach to elucidate origins pyrene-functionalized topologically [2]catenane as well series molecules. For first time, direct evidence differentiating chiroptical signals originating from either topological (local state emission) Euclidean chirality (excimer been discovered. Our work not only establishes novel ideal study mechanism, but also provides theoretical foundation rational design materials future.

Language: Английский

Citations

3
A Light-Responsive Metal–Organic Framework with Perchlorinated Nanographene Ligands DOI
Xin Zheng, Nikita Gupta, Haiying He

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: May 4, 2025

Harnessing water as a sustainable electron source for artificial photosynthesis remains significant challenge. This work presents Alice-MOF-1, novel zirconium metal-organic framework (MOF) incorporating hexatopic ligands with perchlorinated hexa-peri-hexabenzocoronene (HBC) core, photocatalyst CO2 reduction using the terminal donor. Contortion of ligand, induced by edge chlorination, minimizes π-stacking and enhances solubility, enabling direct MOF synthesis. The controlled arrangement chromophores within Alice-MOF-1 is crucial complex multielectron redox reactions. unique ligand architecture promotes symmetry-breaking charge transfer (SBCT), mechanism observed in natural photosynthesis, leading to efficient separation minimal energy loss. Femtosecond transient absorption spectroscopy time-resolved paramagnetic resonance (EPR) confirm formation long-lived radical ions, providing evidence SBCT negligible recombination. These findings demonstrate power MOF-based chromophore assemblies mimic nature's light-harvesting strategies conversion.

Language: Английский

Citations

0
Pd‐Catalyzed [3+6+3+6] Macrocyclizations of Aryl α‐Diazo‐β‐Ketoesters DOI Creative Commons

Zhong Zhuang,

Adiran de Aguirre, Céline Besnard

et al.

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(13), P. 3029 - 3035

Published: May 7, 2024

Abstract Thanks to Pd(II)‐catalysis, an efficient synthesis of unsaturated macrocycles is achieved by [3+6+3+6] condensation cyclic ethers with aryl α‐diazo‐β‐ketoesters. The presence the electron‐rich ester moieties forbids use dirhodium complexes as these diazo decomposition catalysts provoke unforeseen intermolecular C sp 2 −H insertion reactions that derail targeted reactivity. However, Pd(acac) , using high concentration conditions (1 M), a variety 18‐membered (16 examples) afforded both and alkyl reagents. Catalyst selection for either electrophilic aromatic substitution (Rh) or ylide (Pd) pathways are explained computational approaches.

Language: Английский

Citations

0
Unraveling the Origin of Multichannel Circularly Polarized Luminescence in a Pyrene‐Functionalized Topologically Chiral [2]Catenane DOI
Xueli Wang,

Peicong Wu,

Yu Wang

et al.

Angewandte Chemie, Journal Year: 2024, Volume and Issue: unknown

Published: June 4, 2024

Abstract Mechanically interlocked molecules (MIMs) are promising platforms for developing functionalized artificial molecular machines. The construction of chiral MIMs with appealing circularly polarized luminescence (CPL) properties has boosted their potential application in biomedicine and the optical industry. However, there is currently little knowledge about CPL emission mechanism or dynamics these related MIMs. Herein, we demonstrate that time‐resolved (TRCPL) spectroscopy combined transient absorption (TA) offers a feasible approach to elucidate origins pyrene‐functionalized topologically [2]catenane as well series molecules. For first time, direct evidence differentiating chiroptical signals originating from either topological (local state emission) Euclidean chirality (excimer been discovered. Our work not only establishes novel ideal study mechanism, but also provides theoretical foundation rational design materials future.

Language: Английский

Citations

0
Structural and solvent modulation of symmetry-breaking charge-transfer pathways in molecular triads DOI Creative Commons
Chinju Govind, Evangelos Balanikas, Gana Sanil

et al.

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Whereas the photoinduced charge-transfer properties of electron donor-acceptor dyads are now well understood, those symmetric conjugated architectures containing several identical branches have started to be scrutinised much more recently. Here, we report on our investigation dynamics a series formally centrosymmetric triads consisting quadrupolar dihydropyrrolopyrrole core substituted with two diphenylethynyl lateral branches. Using combination time-resolved electronic and vibrational spectroscopies, show that these molecules exhibit rich excited-state dynamics, which includes three different types symmetry-breaking processes depending nature end substituents as solvent: (i) symmetry breaking within core; (ii) charge transfer from one branches; (iii) between This illustrates how molecules, including location exciton, can controlled by fine tuning structural environmental parameters.

Language: Английский

Citations

0