Ultrahigh-Flux Water Nanopumps Generated by Asymmetric Terahertz Absorption

Physical Review Letters, Год журнала: 2024, Номер 132(18)

Опубликована: Май 2, 2024

Controlling active transport of water through membrane channels is essential for advanced nanofluidic devices. Despite advancements in nanopump design using techniques like short-range invasion and subnanometer-level control, challenges remain facilely remotely realizing massive waters transport. Herein, molecular dynamic simulations, we propose an ultrahigh-flux nanopump, powered by frequency-specific terahertz stimulation, capable unidirectionally transporting asymmetric-wettability at room temperature without any external pressure. The key physics behind this terahertz-powered revealed to be the energy flow resulting from asymmetric optical absorption water.

Язык: Английский

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Photo-to-chemical energy transformation: Pioneering photocatalysts, surface and interface engineering

Materials Research Bulletin, Год журнала: 2024, Номер 180, С. 113046 - 113046

Опубликована: Авг. 14, 2024

Язык: Английский

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A visible-light-driven molecular motor based on barbituric acid

Chemical Science, Год журнала: 2023, Номер 14(32), С. 8458 - 8465

Опубликована: Янв. 1, 2023

We present a class of visible-light-driven molecular motors based on barbituric acid. Due to serendipitous reactivity we observed during their synthesis, these possess tertiary stereogenic centre the upper half, characterised by hydroxy group. Using combination femto- and nanosecond transient absorption spectroscopy, dynamics simulations low-temperature

Язык: Английский

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Excited State Dynamics in Unidirectional Photochemical Molecular Motors

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(18), С. 12255 - 12270

Опубликована: Апрель 24, 2024

Unidirectional photochemically driven molecular motors (PMMs) convert the energy of absorbed light into continuous rotational motion. As such they are key components in design machines. The prototypical and most widely employed class PMMs is overcrowded alkenes, where motion by successive photoisomerization thermal helix inversion steps. efficiency depends upon speed rotation, determined rate ground state inversion, quantum yield photoisomerization, which dependent on excited landscape. former has been optimized synthetic modification across three generations alkene PMMs. These improvements have often at expense yield, there remains room for improvement. In this perspective we review application ultrafast spectroscopy to characterize dynamics measurements lead a general mechanism all PMMs, involving subpicosecond decay Franck–Condon populate dark decays within picoseconds via conical intersections with electronic state. model discussed context calculations. Studies PMM photochemical as function solvent suggest exploitation intramolecular charge transfer polarity route controlling yield. A test these ideas first generation motor reveals high degree control over isomerization results pathway fine performance future

Язык: Английский

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Impact of solvation on the photoisomerisation dynamics of a photon-only rotary molecular motor

Communications Physics, Год журнала: 2024, Номер 7(1)

Опубликована: Июль 5, 2024

Abstract The optimization of the quantum efficiency single-molecule light-driven rotary motors typically relies on chemical modifications. While, in isolated conditions, computational methods have been frequently used to design more efficient motors, role played by solvent environment has not satisfactorily investigated. In this study, we multiscale nonadiabatic molecular dynamics simulations working cycle a 2-stroke photon-only motor. results, which display consistent with available transient spectroscopy measurements, predict considerable decrease isomerisation methanol solution respect gas phase. origin such is traced back ability motor establish hydrogen bonds molecules. analysis suggests that modified reduced form will increased efficiency, therefore extending set engineering rules for designing motors.

Язык: Английский

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General strategy for boosting the performance of speed-tunable rotary molecular motors with visible light

Science Advances, Год журнала: 2025, Номер 11(8)

Опубликована: Фев. 19, 2025

Light-driven molecular rotary motors perform chirality-controlled unidirectional rotations fueled by light and heat. This unique function renders them appealing for the construction of dynamic systems, actuating materials, machines. Achieving a combination high photoefficiency, visible-light responsiveness, synthetic accessibility, easy tuning properties within single scaffold is critical these applications but remains longstanding challenge. Herein, series highly photoefficient visible-light–responsive (MMs), featuring various speeds, was obtained convenient one-step formylation their parent motors. strategy greatly improves all aspects performance MMs—red-shifted wavelengths excitation, photoisomerization quantum yields, photostationary state distributions isomers—beyond state-of-the-art light-responsive MM systems. The development this late-stage functionalization MMs opens avenues high-performance machines devices in materials science biological representing major advance toolbox

Язык: Английский

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A photochemical method to evidence directional molecular motions

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Июль 31, 2023

Light driven synthetic molecular motors represent crucial building blocks for advanced machines and their applications. A standing challenge is the development of very fast able to perform rotations with kHz, MHz or even faster frequencies. Central this direct experimental evidence directionality because analytical methods follow motions rarely deliver precise geometrical insights. Here, a general photochemical method elucidation directional presented. In macrocyclization approach motor are restricted forced proceed in two separate ~180° rotation-photoequilibria. Therefore, all four possible photoinduced rotation steps (clockwise counterclockwise directions) can be quantified. Comparison corresponding quantum yields unrestricted delivers unidirectionality. This used any ultrafast cases where no high energy intermediates present during cycle.

Язык: Английский

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A Cost‐Effective Computational Strategy for the Electronic Layout Characterization of a Second Generation Light‐Driven Molecular Rotary Motor in Solution

Journal of Computational Chemistry, Год журнала: 2025, Номер 46(2)

Опубликована: Янв. 11, 2025

ABSTRACT Light‐driven molecular rotary motors are nanometric machines able to convert light into unidirectional motions. Several types of have been developed better respond stimuli, opening new avenues for developing smart materials ranging from nanomedicine robotics. They great importance in the scientific research across various disciplines, but a detailed comprehension underlying ultrafast photophysics immediately after photo‐excitation, that is, Franck–Condon region characterization, is not fully achieved yet. For this aim, it first required rely on an accurate description at ab initio level system potential energy before performing any further step, dynamics. Thus, we present extensive investigation aimed accurately describing electronic structure low‐lying states (electronic layout) rotor region, belonging class overcrowded alkenes: 9‐(2‐methyl‐2,3‐dihydro‐1H‐cyclopenta[a]naphthalen‐1‐ylidene)‐9H‐fluorene. This was chosen since its very interesting more general understanding similar compounds used as rotors, where can be found (whose energetic interplay crucial dynamics) and presence different substituents tune HOMO‐LUMO gap. scope, employed theory levels within time‐dependent density functional framework, presenting also careful comparison adopting post Hartree–Fock methods characterizing conformations involved photocycle. Effects layout functionals, basis sets, environment descriptions, role dispersion correction were all analyzed detail. In particular, treatment solvent effects here considered depth, showing how implicit excited by testing both linear‐response state‐specific formalisms. As main results, chose two cost‐effective (accurate relatively cheap) ground state verified choosing these influence curvature via frequency analysis normal modes vibrations active Raman spectrum. theoretical survey step towards feasible characterization early stage solution during photoisomerization processes wherein multiple might populated upon radiation, leading future molecular‐level interpretation time‐resolved spectroscopies.

Язык: Английский

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Tuning the Photoisomerization Mechanism of Oxindole Switches with Electron-Donating Substituents

The Journal of Physical Chemistry B, Год журнала: 2025, Номер unknown

Опубликована: Апрель 8, 2025

This study investigates the photoreaction mechanism of a hydroxy-substituted oxindole photoswitch using femtosecond transient absorption, fluorescence up-conversion, and computational chemistry. Deprotonation hydroxyl group enhances push-pull character in molecule, allowing tuning photoisomerization from precessional to an axial motion. The neutral form switch exhibits longer excited-state lifetimes, while anionic decays rapidly within 200 fs. Computational models show that deprotonation increases charge transfer accessibility conical intersections. work highlights how varying electron-donating strength substituent tunes designing photoswitches.

Язык: Английский

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Fine Tuning of the Rotational Speed of Light-Driven, Second-Generation Molecular Motors by Fluorine Substitution

The Journal of Physical Chemistry Letters, Год журнала: 2025, Номер unknown, С. 4014 - 4020

Опубликована: Апрель 14, 2025

The elementary steps in the rotation of several second-generation molecular motors are analyzed by finding minimum energy path between metastable and stable states evaluating transition rate within harmonic state theory based on energetics obtained from density functional theory. Comparison with published experimental data shows remarkably good agreement demonstrates predictive capability this approach. While previous measurements Feringa co-workers have shown that a replacement hydrogen atom at stereogenic center fluorine can slow down rate-limiting thermal helix inversion (THI) step raising state, even to extent backreaction ground becomes preferred some cases, we find CH3 group CF3 same site accelerates THI elevating without affecting significantly. Since these two substitutions an opposite effect THI, combination both provide ways fine-tune rotational speed motors.

Язык: Английский

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