Abstract Since the discovery of quantum beats in two-dimensional electronic spectra photosynthetic pigment-protein complexes over a decade ago, origin and mechanistic function these light-harvesting has been extensively debated. The current consensus is that long-lived oscillatory features likely result from electronic-vibrational mixing, however, it remains uncertain if such mixing significantly influences energy transport. Here, we examine interplay between nuclear degrees freedom (DoF)...

We demonstrated one-colour control of activation, excitation and deactivation a fluorescent diarylethene derivative by using 532 nm CW laser at weak output power.

Photosystem II is crucial for life on Earth as it provides oxygen a result of photoinduced electron transfer and water splitting reactions. The excited state dynamics the photosystem II-reaction center (PSII-RC) has been matter vivid debate because absorption spectra embedded chromophores significantly overlap hence extremely difficult to distinguish transients. Here, we report two-dimensional electronic-vibrational spectroscopic study PSII-RC. simultaneous resolution along both visible...

Introducing appropriate artificial components into natural biological systems could enrich the original functionality. To expand available wavelength range of photosynthetic bacterial light-harvesting complex 2 (LH2 from Rhodopseudomonas acidophila 10050), fluorescent dye (Alexa Fluor 647: A647) was covalently attached to N- and C-terminal Lys residues in LH2 α-polypeptides with a molar ratio A647/LH2 ≃ 9/1. Fluorescence transient absorption spectroscopies revealed that intracomplex energy...

Excited-state aromaticity is one of the most widely applied concepts in field chemistry, often used as a rational guideline for predicting conformational changes cyclic π-conjugated systems induced by photoexcitation. Yet, details relationship between corresponding photoinduced electronic and structural dynamics have remained unclear. In this work, we femtosecond transient absorption time-resolved time-domain Raman spectroscopies to track nonequilibrium planarization cyclooctatetraene (COT)...

Excited-state aromaticity is one of the most widely applied concepts in field chemistry, often used as a rational guideline for predicting conformational changes cyclic π-conjugated systems induced by photoexcitation. Yet, details relationship between corresponding photoinduced electronic and structural dynamics have remained unclear. In this work, we femtosecond transient absorption time-resolved time-domain Raman spectroscopies to track nonequilibrium planarization cyclooctatetraene (COT)...

Solvent polarity dependence of photochromic reactions such as cyclization and cycloreversion a diarylethene derivative, 1,2-bis(2-methyl-3-benzothienyl)perfluorocyclopentene, was investigated by steady-state spectroscopic femtosecond laser photolysis methods. For the reaction, it revealed that quantum yield decreased with an increase in solvent polarities, mainly due to decrease fraction conformer C2 symmetry favorable for cyclization. This result indicated branching ratio deactivation...

Although photoinduced proton-coupled electron transfer (PCET) plays an essential role in photosynthesis, a full understanding of the mechanism is still lacking due to complex nonequilibrium dynamics arising from strongly coupled electronic and nuclear degrees freedom. Here we report PCET biomimetic model system investigated by means transient IR two-dimensional electronic–vibrational (2DEV) spectroscopies, spectroelectrochemistry (IRSEC), calculations utilizing long-range-corrected hybrid...

The role of molecular vibration in photoinduced electron transfer (ET) reactions has been extensively debated recent years. In this study, we investigated vibrational wavepacket dynamics a model ET system consisting an organic dye molecule as acceptor dissolved various donating solvents. By using broad band pump–probe (BBPP) spectroscopy with visible laser pulses sub-10 fs duration, coherent wavepackets naphthacene frequencies spanning 170–1600 cm–1 were observed the time domain. coherence...

Excited state proton transfer (ESPT) is thought to be responsible for the photostability of biological molecules, including DNA and proteins, natural dyes such as indigo. However, mechanistic role solvent interaction in driving ESPT not well understood. Here, electronic excited deactivation dynamics indigo carmine (InC) mapped by visible pump-infrared probe two-dimensional electronic-vibrational (2DEV) spectroscopy complemented structure calculations. The observed reveal notable differences...

Abstract The importance of green light for driving natural photosynthesis has long been underappreciated, however, under the presence strong illumination, actually drives more efficiently than red light. This is absorbed by mixed vibronic Q y -Q x states, arising from chlorophyll (Chl)-Chl interactions, although almost nothing known about these states. Here, we employ polarization-dependent two-dimensional electronic-vibrational spectroscopy to study origin and dynamics states...

Two-dimensional electronic–vibrational spectroscopy (2DEVS) is an emerging spectroscopic technique which exploits two different frequency ranges for the excitation (visible) and detection (infrared) axes of a 2D spectrum. In contrast to degenerate techniques, such as electronic or infrared spectroscopy, spectral features 2DEV spectrum report cross correlations between fluctuating vibrational energy gaps rather than autocorrelations in spectroscopies. The center line slope reports on this...

The photosystem II core complex (PSII-CC) is the smallest subunit of oxygenic photosynthetic apparatus that contains antennas and a reaction center, which together allow for rapid energy transfer charge separation, ultimately leading to efficient solar conversion. However, there lack consensus on interplay between separation dynamics complex. Here, we report application two-dimensional electronic-vibrational (2DEV) spectroscopy spinach PSII-CC at 77 K. simultaneous temporal spectral...

The reaction dynamics of excited-state intramolecular proton transfer (ESIPT) 2,2′-dihydroxyazobenzene (2,2′-DHAB) was investigated by means white-light supercontinuum femtosecond transient absorption spectroscopy. A coherent in-phase oscillation observed in the entire wavelength range where stimulated emission photoproduct is dominant. This result indicates that transition strength product state dynamically modulated a nuclear wavepacket motion (non-Condon effect). vibration assigned to...

Delocalized biradicals have been extensively studied because of fundamental interests to singlet and several potential applications such as two-photon absorption materials. However, many the biradical studies only focus on static properties rigid molecular structures. It is expected that delocalized are sensitive subtle changes structures their local environments. Therefore, dynamic system will give further insight into stable radical chemistry. In this study, we directly probe ultrafast...

A functional linkage between light-harvesting and photocatalytic components is a pivotal issue for using solar energy in chemical conversions; however, this concept far from being practically realized. Here, we constructed system that integrates an artificially extended photosynthetic complex 2 (LH2) 1-reaction center (RC) core (LH1-RC). biohybrid LH2, whose ability was by covalently attached hydrophobic fluorophore ATTO647N (LH2-ATTO) to cover the absorption gap of assembled with LH1-RC...

Organic-inorganic nanohybrids using semiconductor nanocrystals (NCs) coordinated with aromatic organic molecules have been widely studied in the fields of optoelectronic materials, such as solar cells, photocatalysis, and photon upconversion. In these coordination bonds ligand are usually assumed to be stable during optical processes. However, this assumption is not always valid. study, we demonstrate that between NCs by carboxyl groups displaced quasi-reversibly light irradiation zinc...

Energy transfer dynamics in monomer and dimer of the photosystem II core complex (PSII-CC) was investigated by means femtosecond transient absorption (TA) spectroscopy. There is no profound difference between TA weak excitation intensity condition (≤21 nJ). However, fast recovery ground state bleach pronounced at higher intensities, dependence more significant than that monomer. This result indicates efficient exciton-exciton annihilation taking place due to energy two units. The reproduced...

Photosynthetic light-harvesting (LH) systems consist of photosynthetic pigments, which are non-covalently self-assembled with protein scaffolds in many phototrophs and attain highly efficient excitation energy transfer via ultrafast dynamics. In this study, we constructed a biohybrid LH system composed an complex (LH2) from Rhodoblastus acidophilus strain 10050 hydrophobic fluorophore ATTO647N (ATTO) as extrinsic antenna the lipid bilayer. Through addition ATTOs into solution...

Molecular design of dual-fluorescent probes requires precise adjustment the energy levels two excited states and barrier between them. While hybridized local charge-transfer (HLCT) state has been recently focused as an important for high emission efficiency with a tunable level, dual involving HLCT only achieved excited-state intramolecular proton transfer (ESIPT) system. Here, series molecules conjugation enhancement (ESCE) motif is presented first case. The level adjusted by changing...

Single-molecule fluorescence spectroscopy is a powerful tool to investigate the physical properties of individual molecules. Yet, elucidating fast fluctuation dynamics freely diffusing single molecules in solution at room temperature, where variety chemical and biological processes occur, remains challenging. In this study, we report on excitation correlation (FECS) room-temperature solutions, which enables study spontaneous spectrum with microsecond time resolution. By employing Fourier...

Femtosecond transient absorption (TA) and picosecond time-resolved fluorescence (TRF) spectroscopies were applied to the charge separation (CS) dynamics of 10-cyano-9,9′-bianthryl (CBA) in a normal polar solvent, acetonitrile (Acn), highly viscous room temperature ionic liquid (IL), N,N-diethyl-N-methyl-N-(methoxyethyl)ammonium tetrafluoroborate (DemeBF4). The primary CS took place within ultrafast sub-100 fs time range both solvents, which was completely independent diffusive solvation....

Photochemical reactions occur in the electronically excited state, which is effectively represented by a multidimensional potential energy surface (PES) with vast degree of freedom nuclear coordinates. The elucidation intricate shape PES constitutes an important topic field photochemistry and has long been studied both experimentally theoretically. Recently, fully time-domain resonant two-dimensional Raman spectroscopy emerged as potentially powerful tool to provide unique information about...