Theoretical Insights Into the Excited State Double Proton Transfer Mechanism of Deep Red Pigment Alkannin

The Journal of Physical Chemistry A, Год журнала: 2018, Номер 122(5), С. 1200 - 1208

Опубликована: Янв. 10, 2018

As the most important component of deep red pigments, alkannin is investigated theoretically in detail based on time-dependent density functional theory (TDDFT) method. Exploring dual intramolecular hydrogen bonds (O1–H2···O3 and O4–H5···O6) alkannin, we confirm O1–H2···O3 may play a more role first excited state than O4–H5···O6 one. Infrared (IR) vibrational analyses subsequent charge redistribution also support this viewpoint. Via constructing S1-state potential energy surface (PES) searching transition (TS) structures, illuminate double proton transfer (ESDPT) mechanism stepwise process that can be launched by bond wire gas state, acetonitrile (CH3CN) cyclohexane (CYH) solvents. We present novel polar aprotic solvents contribute to first-step (PT) S1 nonpolar roles lowering barrier second-step PT reaction.

Язык: Английский

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Excited‐State Intramolecular Proton Transfer (ESIPT) for Optical Sensing in Solid State

Advanced Optical Materials, Год журнала: 2021, Номер 9(23)

Опубликована: Фев. 18, 2021

Abstract Excited‐state intramolecular proton transfer (ESIPT) process brings about ultrafast keto‐enol tautomerism, which simultaneously induces the unique four‐leveled energy state cycle and concomitant multi‐emissions. Such transformation is easily affected by environmental conditions, leading to intricate spectral responses. In contrast with widely reported researches that inclined solution systems dissolved ESIPT molecules, materials including small organic metal‐organic materials, covalent‐organic frameworks, so on, can be formed in solid are emerging recent years, bringing more scientific information novel applications for family of materials. this short review, progress different types these will introduced, especially their optical sensing performances mechanisms, like responses external physical stimulations (pressure, temperature, light), solvent polarities, pH, ions, molecule compounds. And potential photophysical photochemical also surveyed.

Язык: Английский

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Dynamics of Excitons in Conjugated Molecules and Organic Semiconductor Systems

Chemical Reviews, Год журнала: 2022, Номер 122(9), С. 8487 - 8593

Опубликована: Март 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.

Язык: Английский

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Stimuli-Induced Reversible Proton Transfer for Stimuli-Responsive Materials and Devices

Accounts of Chemical Research, Год журнала: 2021, Номер 54(9), С. 2216 - 2226

Опубликована: Апрель 21, 2021

ConspectusStimuli-responsive materials have a great potential in various novel photoelectric devices, such as self-adaptive adjustment intelligent detection, molecular computers with information storage capability, camouflage and anticounterfeiting display, energy-saving displays, others. However, progress related areas has been relatively slow because of the lack high-performance smart limitations available reaction mechanisms currently. To address these problems fundamentally, new need to be designed developed, learning from nature is an effective method achieve this long-awaited target, mimicking proton transfer processes at molecular/supramolecular level. The stimuli-induced reversible system composed that release or capture protons response stimuli switch molecules control color and/or fluorescence modulation by protons, it applied stimuli-responsive including bistable electronic/electrochromic electrofluorochromic water-jet rewritable paper, visible-light-responsive mechanochromic materials.To help researchers gain deep insight into transfer, we attempted summarize its mechanism design principle, discuss strategies prepare devices. This Account discusses different systems which color/fluorescence change induced process under stimuli, electric field, water, light, heat, stress. Relative very promising applications well their performance especially for environmentally friendly devices are then summarized, electrochromic paper. Meanwhile, focus on key influence factors useful additives improving device's performance. At last, challenges bottlenecks faced based proposed. Moreover, put forward some suggestions solving limitations.These exciting results reveal extremely attractive possess next generation energy resource saving environmental protection display. We hope further prospers field discoloration next-generation green displays.

Язык: Английский

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Thermally Activated Fluorescence vs Long Persistent Luminescence in ESIPT-Attributed Coordination Polymer

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(6), С. 2726 - 2734

Опубликована: Янв. 10, 2022

Excited-state intramolecular proton transfer (ESIPT) molecules demonstrating specific enol-keto tautomerism and the related photoluminescence (PL) switch have wide applications in displaying, sensing, imaging, lasing, etc. However, an ESIPT-attributed coordination polymer showing alternative PL between thermally activated fluorescence (TAF) long persistent luminescence (LPL) has never been explored. Herein, we report assembly of a dynamic Cd(II) (LIFM-101) from ESIPT-type ligand, HPI2C (5-(2-(2-hydroxyphenyl)-4,5-diphenyl-1H-imidazol-1-yl)isophthalic acid). For first time, TAF and/or color-tuned LPL can be achieved by controlling temperature under guidance ESIPT excited states. Noteworthily, twisted structure ligand LIFM-101 achieves effective mixture higher-energy states, leading to ISC (intersystem crossing)/RISC (reverse intersystem crossing) energy high-lying keto-triplet state (Tn(K*)) singlet (S1(K*)). Meanwhile, experimental theoretical results manifest occurrence probability relevance among RISC, ISC, internal conversion (IC) this unique polymer, unprecedented TAF/LPL switching mechanism, paving way for future design application advanced optical materials.

Язык: Английский

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