Dynamics of Excitons in Conjugated Molecules and Organic Semiconductor Systems

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(9), P. 8487 - 8593

Published: March 17, 2022

The exciton, an excited electron-hole pair bound by Coulomb attraction, plays a key role in photophysics of organic molecules and drives practically important phenomena such as photoinduced mechanical motions molecule, photochemical conversions, energy transfer, generation free charge carriers, etc. Its behavior extended π-conjugated disordered films is very different rich compared with exciton inorganic semiconductor crystals. Due to the high degree variability systems themselves, not only exerts changes on that carry it but undergoes its own during all phases lifetime, is, birth, conversion transport, decay. goal this review give systematic comprehensive view molecular assemblies at evolution emphasis rates typical for dynamic picture various consequences above dynamics. To uncover variety behavior, details formation, conversion, direct reverse intersystem crossing, radiative nonradiative decay are considered systems, where these processes lead or influenced static disorder, distribution symmetry breaking, reactions, electron proton structural rearrangements, coupling vibrations intermediate particles, dissociation annihilation well.

Language: Английский

---

Accelerating symmetry-breaking charge separation in a perylenediimide trimer through a vibronically coherent dimer intermediate

Nature Chemistry, Journal Year: 2022, Volume and Issue: 14(7), P. 786 - 793

Published: April 25, 2022

Language: Английский

---

Coherent Two-Dimensional and Broadband Electronic Spectroscopies

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(3), P. 4257 - 4321

Published: Jan. 17, 2022

Over the past few decades, coherent broadband spectroscopy has been widely used to improve our understanding of ultrafast processes (e.g., photoinduced electron transfer, proton and proton-coupled transfer reactions) at femtosecond resolution. The advances in laser technology along with development nonlinear multidimensional enabled further insights into energy carrier relaxation complex biological material systems. New discoveries interpretations have led improved design principles for optimizing photophysical properties various artificial In this review, we first provide a detailed theoretical framework both two-dimensional electronic (2DES). We then discuss selection experimental approaches considerations 2DES best practices data processing analysis. Finally, review several examples where were employed reveal mechanisms photoinitiated molecular, biological, end brief perspective on future techniques themselves their potential answer an even greater range scientific questions.

Language: Английский

---

Leveraging excited-state coherence for synthetic control of ultrafast dynamics

Nature, Journal Year: 2020, Volume and Issue: 582(7811), P. 214 - 218

Published: June 11, 2020

Language: Английский

---

Interplay of vibrational wavepackets during an ultrafast electron transfer reaction

Nature Chemistry, Journal Year: 2020, Volume and Issue: 13(1), P. 70 - 77

Published: Dec. 7, 2020

Language: Английский

---

A Review on Characterization Techniques for Carbon Quantum Dots and Their Applications in Agrochemical Residue Detection

Journal of Fluorescence, Journal Year: 2022, Volume and Issue: 32(2), P. 449 - 471

Published: Jan. 22, 2022

Language: Английский

---

From a one-mode to a multi-mode understanding of conical intersection mediated ultrafast organic photochemical reactions

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(8), P. 2643 - 2687

Published: Jan. 1, 2023

Over the last few decades, conical intersections (CoIns) have grown from theoretical curiosities into common mechanistic features of photochemical reactions, whose function is to funnel electronically excited molecules back their ground state in regions where potential energy surfaces (PESs) two electronic states become degenerate. Analogous transition thermal chemistry, CoIns appear as transient structures providing a kinetic bottleneck along reaction coordinate. However, such not associated with probability crossing an barrier but rather decay full "line" connected by non-reactive modes, intersection space (IS). This article will review our understanding factors controlling CoIn mediated ultrafast taking physical organic chemist approach discussing number case studies for small and photoactive proteins. Such discussion be carried out first introducing "standard" one-mode model based on Landau-Zener (LZ) theory describe reactive event intercepting, locally, single direction, then modern perspective effects phase matching multiple modes same local event, thus redefining expanding description The direct proportionality between slope (or velocity) one mode at widely applied fundamental principle that follows LZ model, yet it fails provide complete reactions coordinate changes IS. We show these situations, particular focussing rhodopsin double bond photoisomerization, mandatory consider additional molecular relationship approaching IS, hence key photochemistry those modes. anticipate this qualitative should considered rational design any process, impacting various fields research ranging photobiology light-driven devices.

Language: Английский

---

Phase-Coherent Charge Transport through a Porphyrin Nanoribbon

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(28), P. 15265 - 15274

Published: July 7, 2023

Since the early days of quantum mechanics, it has been known that electrons behave simultaneously as particles and waves, now electronic devices can harness this duality. When are shrunk to molecular scale, is unclear under what conditions does electron transmission remain phase-coherent, molecules usually treated either scattering or redox centers, without considering wave–particle duality charge carrier. Here, we demonstrate remains phase-coherent in porphyrin nanoribbons connected graphene electrodes. The act Fabry–Pérot interferometers allow for direct probing transport mechanisms throughout several regimes. Through electrostatic gating, observe interference fringes strongly correlated conductance across multiple oxidation states. These results a platform use interferometric effects single-molecule junctions, opening up new avenues studying coherence spintronic devices.

Language: Английский

---

Spin–vibronic coherence drives singlet–triplet conversion

Nature, Journal Year: 2023, Volume and Issue: 620(7975), P. 776 - 781

Published: July 19, 2023

Language: Английский

---

Coherence in Chemistry: Foundations and Frontiers

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(21), P. 11641 - 11766

Published: Oct. 23, 2024

Coherence refers to correlations in waves. Because matter has a wave-particle nature, it is unsurprising that coherence deep connections with the most contemporary issues chemistry research (e.g., energy harvesting, femtosecond spectroscopy, molecular qubits and more). But what does word "coherence" really mean context of molecules other quantum systems? We provide review key concepts, definitions, methodologies, surrounding phenomena chemistry, we describe how terms "quantum coherence" refer many different chemistry. Moreover, show these notions are related concept an interference pattern. indeed complex, ambiguous definitions may spawn confusion. By describing contexts for sciences, aim enhance understanding communication this broad active area

Language: Английский

---