記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Science  

希土類錯体は色再現度の高いディスプレイなどの発光材料への応用が期待されているが、その薄膜中における発光機構が不明なことが新規デバイス開発のボトルネックとなっていた。本成果では、三価ユウロピウム（Eu(III)）錯体を用いた薄膜における発光機構を1兆分の1秒の時間分解能で逐次解析することによって詳細に明らかにした。発光機構を基に薄膜内の光エネルギー移動効率100%、錯体単体と比較して400倍の発光強度を達成した。

DOI： 10.1039/D3SC01817B

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Singlet fission (SF), converting a singlet excited state into a spin-correlated triplet-pair state, is an effective way to generate a spin quintet state in organic materials. Although its application to photovoltaics as an exciton multiplier has been extensively studied, the use of its unique spin degree of freedom has been largely unexplored. Here, we demonstrate that the spin polarization of the quintet multiexcitons generated by SF improves the sensitivity of magnetic resonance of water molecules through dynamic nuclear polarization (DNP). We form supramolecular assemblies of a few pentacene chromophores and use SF-born quintet spins to achieve DNP of water-glycerol, the most basic biological matrix, as evidenced by the dependence of nuclear polarization enhancement on magnetic field and microwave power. Our demonstration opens a use of SF as a polarized spin generator in bio-quantum technology.

リポジトリ公開URL： https://hdl.handle.net/2324/7234644

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jpcc.1c04283

記述言語：英語   掲載種別：研究論文（学術雑誌）  

熱活性化遅延蛍光（TADF）の設計は、ESTを小さくするために遷移が関わる軌道の重なりを小さくしなければならないが、発光特性の観点からは重なりを大きくする必要があり本質的な矛盾が内在している。ドナー‐アクセプター型のTADF材料のDA二面角揺らぎを制御した分子に対する時間分解赤外分光と量子化学計算により励起状態での構造変化の比較検討を元に、二面角揺らぎがこの矛盾を解決する糸口になり得ると提案した。

DOI： 10.1063/5.0029608

その他リンク： https://doi.org/10.1063/5.0029608

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jpca.0c02224

その他リンク： https://doi.org/10.1021/acs.jpca.0c02224

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.5127993

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

熱活性化遅延蛍光は高効率有機発光ダイオードを達成する新しい原理として注目を集めているが、微視的な原理はいまだに明らかになっていない。開発を促進するためにも、分子レベルでの発光メカニズムを解明することは急務である。本論文では、同様の構造を持つにもかかわらず異なる熱活性化遅延蛍光能を持つ分子群に注目し、本研究室で独自に開発してきた時間分解赤外分光を用いて励起状態の分子の立体構造変化を追跡した。結果として、励起状態で分子の立体構造変化が抑制されている場合に発光能が著しく高いことがわかった。この発見は熱活性遅延蛍光分子のデザイン指針の確立に大きく貢献するものである。

DOI： 10.1021/acs.jpclett.9b00810

その他リンク： https://pubs.acs.org/doi/abs/10.1021/acs.jpclett.9b00810

記述言語：英語   掲載種別：研究論文（学術雑誌）  

オプトエレクトロニクスで非常に重要な位置づけとなっている新規材料鉛ハライドペロブスカイトについて、その特異な電子物性を理解する鍵として強誘電材料としても側面を議論した論文。印加された電場に対して非常に大きく応答できる高誘電率といった性質から、注入されたキャリアが周囲に微視的な強誘電相転移を誘起する可能性について言及し、Ferroelectric polaronという全く新しい概念を提唱した。

DOI： 10.1038/s41563-018-0068-7

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1126/sciadv.1701469

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/NCHEM.2784

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1126/sciadv.1701217

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1126/science.aaf9570

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1103/PhysRevB.91.195306

記述言語：英語   出版者・発行元：Nature Communications  

In recent years, thermally activated delayed fluorescence (TADF) has attracted intense attention owing to its straightforward application to high-efficiency organic light-emitting diodes. Further, to develop high-performance TADF materials, many researchers have designed novel molecules that have a small energy gap between the lowest excited singlet and triplet states (ΔEST), and detailed analysis suggests a significant contribution of higher-lying excited states for spin flipping processes. In this study, we demonstrate a peculiar thermal behaviour of emission decay of a donor–acceptor type TADF molecule, TMCz-BO, which seems like thermal deactivation of delayed fluorescence that can be explained without a negative ΔEST by comprehensive kinetic analysis across various temperatures and solvents. While the activation energy has previously been treated as being temperature-independent, we stress that it should be a dynamic parameter affected by changing the solvent-solute interaction with the environmental temperature, especially in the case of a small energy gap.

DOI： 10.1038/s41467-025-59910-z

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出版者・発行元：Aggregate  

Organic lasers hold great promise for enabling a new class of future optoelectronics. Consequently, the development of new organic semiconductors as gain media has recently been the subject of significant interest. The molecular design principle based on Einstein coefficients has been validated for achieving high gain, with para-phenylene-vinylene scaffolds recognized as one of the most crucial frameworks. In this study, we develop a stilbene tetramer derivative, QSBCz, which has significantly increased conjugation compared to the highly efficient laser material, BSBCz, resulting in a remarkably high radiative decay rate and a large gain cross-section. However, we find that the optical losses play a significant role in the light amplification of QSBCz. Indeed, a comprehensive understanding and suppression of detrimental optical loss pathways throughout the lasing process are essential, whereas the losses intrinsically associated with molecules have not been well considered. Although host–guest systems are helpful in preventing concentration quenching in aggregated states, this study reveals notable losses when using common host molecules such as 4,4′-bis(9H-carbazol-9-yl)biphenyl (CBP) and mCBP. In contrast, a BSBCz derivative is successfully employed as the host, leading to improved stimulated emission amplification. These findings indicate the importance of host–emitter interactions in lasing properties and highlight the necessity to optimize host materials for developing new laser dyes.

DOI： 10.1002/agt2.70030

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出版者・発行元：Chemphotochem  

Development of near-infrared (NIR)-light-driven photocatalytic hydrogen (H<inf>2</inf>) production is indispensable for an efficient use of solar energy in a sustainable society. Herein, a strategy is reported for achieving higher quantum yields of NIR-light-driven photocatalytic H<inf>2</inf> production using salts of diprotonated dodecaphenylporphyrin (H<inf>4</inf>DPP²⁺(X⁻)<inf>2</inf>), showing large saddle distortion as organic photosensitizers and platinum nanoparticles as catalysts. When a perchlorate ion (ClO<inf>4</inf>⁻) is employed as a counter ion (X⁻) of H<inf>4</inf>DPP²⁺(X⁻)<inf>2</inf>, the quantum yield of the photocatalytic H<inf>2</inf> production reaches to 36% by excitation at 750 nm, which is the highest value among those of NIR-light-driven H<inf>2</inf> production reported so far. Such a drastic enhancement of the quantum yield is achieved by selection of X⁻ as an appropriate counter anion of H<inf>4</inf>DPP²⁺, judging from second-order rate constants of photoinduced electron transfer (ET) from electron donors to ³(H<inf>4</inf>DPP²⁺(X⁻)<inf>2</inf>)* and the reorganization energy of ET for H<inf>4</inf>DPP²⁺(X⁻)<inf>2</inf>.

DOI： 10.1002/cptc.202500009

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記述言語：英語   出版者・発行元：Journal of Chemical Physics  

Introducing heavy atoms, or replacing atoms with heavier ones, is a routine approach for accelerating spin-flipping photophysical processes. However, predicting its impact on phosphorescence efficiency is not straightforward. Herein, we report an unexpected consequence of bromine-to-iodine substitution in a bromothienyl diketone derivative, TIPS-BrTn, that exhibits outstanding room-temperature phosphorescence (RTP) in cyclohexane solution. Contrary to our expectation, the iodo-congener TIPS-ITn exhibited feeble photoluminescence, which we confirmed as RTP by ultrafast spectroscopy. Further experimental and theoretical studies revealed that, in the T<inf>1</inf> state, an excited-state symmetry breaking occurred on TIPS-ITn while TIPS-BrTn preserved the centrosymmetric geometry. We identified the driving force for the symmetry breaking as an intramolecular two-center three-electron bonding interaction between iodine and carbonyl oxygen in the (n,π*) excited state. Consequently, while the direct T<inf>1</inf>-S<inf>0</inf> spin-orbit coupling (SOC) in TIPS-BrTn is symmetry-forbidden and zero, that of TIPS-ITn is non-zero due to the loss of centrosymmetry, thereby accelerating nonradiative T<inf>1</inf>-S<inf>0</inf> decay to diminish the RTP. Importantly, the phosphorescence rate constant is not solely dictated by the direct T<inf>1</inf>-S<inf>0</inf> SOC; instead, it can be rationalized by the intensity borrowing from higher singlet states. Thus, our work highlights the importance of controlling molecular symmetry, which could suppress the direct T<inf>1</inf>-S<inf>0</inf> SOC and lead to a preferential acceleration of radiative decay over nonradiative decay for achieving efficient RTP.

DOI： 10.1063/5.0255535

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記述言語：英語   出版者・発行元：Communications Chemistry  

Photoinduced metal-to-ligand (or ligand-to-metal) charge-transfer (CT) states in metal complexes have been extensively studied toward the development of luminescent materials. However, previous studies have mainly focused on CT transitions between d- and π-orbitals. Herein, we report the demonstration of CT emission from 4f- to π-orbitals using a trivalent europium (Eu(III)) complex, supported by both experimental and theoretical analyses. The Eu(III) complex exhibits an eight-coordination structure, comprising three anionic nitrates and two neutral electron-donating ligands containing a carbazole unit. The diffuse reflectance spectrum of the complex displays an absorption band at 440 nm and time-resolved emission analyses reveal a characteristic emission band at 550 nm. Comparative studies employing a trivalent gadolinium (Gd(III)) complex, alongside quantum chemical analyses, confirm that the observed absorption and emission bands are associated with CT transitions between π- and 4f-orbitals. The observation of CT emission based on the 4f-orbital offers novel insights into the field of molecular luminescence science and technology.

DOI： 10.1038/s42004-025-01420-6

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記述言語：英語   出版者・発行元：Angewandte Chemie International Edition  

Although a widely used and important industrial chemical, carbon disulfide (CS<inf>2</inf>) poses a number of hazards due to its volatility and toxicity. As such, the development of multifunctional materials for the selective capture and easy recognition of CS<inf>2</inf> is one of the crucial issues. Herein, we demonstrate completely selective CS<inf>2</inf> adsorption among trials involving H<inf>2</inf>O, alcohols, volatile organic compounds (including thiol derivatives), N<inf>2</inf>, H<inf>2</inf>, O<inf>2</inf>, CH<inf>4</inf>, CO, NO, and CO<inf>2</inf>. We also showcase its fine detection using remarkable luminescent response in a gold(I)-based metal−organic framework (MOF) of {Zn^II(pz)[Au^I(CN)<inf>2</inf>]<inf>2</inf>} (pz=pyrazine; 1) with a two-fold interpenetration network. Ex situ single crystal X-ray diffraction for 1 and CS<inf>2</inf>-accommodated 1 suggested that the Au ⋅⋅⋅ Au atoms are not only luminescent centers but also act as interaction sites for CS<inf>2</inf> modulating the Au ⋅⋅⋅ Au contacts. These experiments revealed the specificity of CS<inf>2</inf> and how changes in the CS<inf>2</inf>-induced structure. Based on the obtained structural transformation, 1 exhibited a sensitive detecting ability for CS<inf>2</inf> with an ultrafast response time of less than 10 s. Moreover, ex situ time-resolved photoluminescence analyses developed in this work implied that CS<inf>2</inf> varied the energetic relaxation at the excited states related to the luminescent efficiency of the resultant MOF system.

DOI： 10.1002/anie.202413830

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記述言語：英語   出版者・発行元：Journal of the American Chemical Society  

Light-driven spin hyperpolarization of organic molecules is a crucial technique for spin-based applications such as quantum information science (QIS) and dynamic nuclear polarization (DNP). Synthetic chemistry provides the design of spins with atomic precision and enables the scale-up of individual spins to hierarchical structures. The high designability and extended pore structure of metal-organic frameworks (MOFs) can control interactions between spins and guest molecules. However, the effective design of polarizing radical electron spins by photoexcitation in MOFs has been unexplored. Here, we show that it is possible to effectively hyperpolarize radical electron spins by harvesting mobile excitons in MOFs. As a proof of concept, we introduce 4-carboxy TEMPO molecules as electron spins into MOF-525, which contains an array of porphyrin chromophores, and demonstrate that this light-harvesting MOF system generates a spin-polarized excited quartet state and doublet ground state even by doping a small amount of electron spins. The current material design leads to the creation of highly spin-polarized nanospaces that can be used for quantum sensing and DNP by efficiently generating high-spin polarization in MOFs doped with small amounts of electron spins to prevent spin relaxation.

DOI： 10.1021/jacs.4c14916

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記述言語：英語   出版者・発行元：Chemical Communications  

Peripherally unsubstituted dioxadiaza[8]circulene, as the first example of structurally identified pristine hetero[8]circulene, was synthesized by the substituent detachment reactions. The solid-state structures and photophysical properties were analysed to elucidate intermolecular interactions. Herzberg-Teller type emission was considered to explain the optical behavior.

DOI： 10.1039/d4cc05539j

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記述言語：英語   出版者・発行元：Advanced Materials  

Two-dimensional perovskites containing an organic fluorophore can be a unique emitter for light-emitting diodes (LEDs). However, external quantum efficiencies (EQEs) of fluorophore-containing perovskite LEDs reported thus far are still very low. In this study, these are able to boost the EQE to ≈10% by choosing an organic fluorophore with appropriate energy levels for the perovskite structure organization. In the fluorophore-containing perovskite LEDs, carrier transport and exciton formation take place in the perovskite's metal halide framework, thereby avoiding the direct formation of nonradiative triplet excitons on the organic fluorophores. Subsequently, the bright triplet excitons formed in the metal halide framework are transferred to form the radiative singlet states of the organic fluorophores, leading to efficient electroluminescence (EL) from the organic fluorophores regularly dispersed inside the perovskite structure. Unexpectedly higher light-outcoupling efficiency, which is caused by the light scattering in the polycrystalline perovskite layer, will be another reason for efficient EL. These findings will contribute toward the fabrication of LED-based products with high performance at a low cost.

DOI： 10.1002/adma.202408775

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出版者・発行元：Advanced Functional Materials  

Photomechanical crystals have applications in light-fueled actuators and soft robots. Herein, light-responsive, versatile, anthraquinone dye crystal oscillators actuated via natural vibrations that are resonated by a photothermal effect are described. A black needle-shaped crystal cantilever oscillates at 70 Hz in the first mode of natural vibration upon irradiation by broad-wavelength light ranging from the ultraviolet through the visible to the near-infrared, and also under continuous-wavelength light (400–2000 nm). The second and third natural vibration modes are induced at higher frequencies (530 and 1350 Hz) and evidence complex flagellum-like motions. The frequency can be readily tuned by moving the support of a crystal piece; this is analogous to playing a guitar. The crystal exhibits high durability (more than 10 000 cycles): the high elasticity prevents deterioration. Oscillatory motions can be designed via simulations using finite element analysis. This work will facilitate the use of photomechanical crystals in light-fueled soft robots.

DOI： 10.1002/adfm.202410671

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記述言語：英語   出版者・発行元：Advanced Science  

The singlet fission characteristics of aqueous nanoparticles, self-assembled from ion pairs of tetracene dicarboxylic acid and various amines with or without chirality, are thoroughly investigated. The structure of the ammonium molecule, the counterion, is found to play a decisive role in determining the molecular orientation of the ion pairs and its regularity, spectroscopic properties, the strength of the intermolecular coupling between the tetracene chromophores, and the consequent singlet fission process. Using chiral amines has led to the formation of crystalline nanosheets and efficient singlet fission with a triplet quantum yield as high as 133% ±20% and a rate constant of 6.99 × 10⁹ s⁻¹. The chiral ion pairs also provide a separation channel to free triplets with yields as high as 33% ±10%. In contrast, nanoparticles with achiral counterions do not show singlet fission, which gave low or high fluorescence quantum yields depending on the size of the counterions. The racemic ion pair produces a correlated triplet pair intermediate by singlet fission, but no decorrelation into two free triplets is observed, as triplet-triplet annihilation dominates. The introduction of chirality enables higher control over orientation and singlet fission in self-assembled chromophores. It provides new design guidelines for singlet fission materials.

DOI： 10.1002/advs.202405864

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記述言語：英語   出版者・発行元：Chemical Science  

We report metal-free organic 1,2-diketones that exhibit fast and highly efficient room-temperature phosphorescence (RTP) with high colour purity under various conditions, including solutions. RTP quantum yields reached 38.2% in solution under Ar, 54% in a polymer matrix in air, and 50% in crystalline solids in air. Moreover, the narrowband RTP consistently dominated the steady-state emission, regardless of the molecular environment. Detailed mechanistic studies using ultrafast spectroscopy, single-crystal X-ray structure analysis, and theoretical calculations revealed picosecond intersystem crossing (ISC) followed by RTP from a planar conformation. Notably, the phosphorescence rate constant k<inf>p</inf> was unambiguously established as ∼5000 s⁻¹, which is comparable to that of platinum porphyrins (representative heavy-metal phosphor). This inherently large k<inf>p</inf> enabled the high-efficiency RTP across diverse molecular environments, thus complementing the streamlined persistent RTP approach. The mechanism behind the photofunction has been elucidated as follows: (1) the large k<inf>p</inf> is due to efficient intensity borrowing of the T<inf>1</inf> state from the bright S<inf>3</inf> state, (2) the rapid ISC occurs from the S<inf>1</inf> to the T<inf>3</inf> state because these states are nearly isoenergetic and have a considerable spin-orbit coupling, and (3) the narrowband emission results from the minimal geometry change between the T<inf>1</inf> and S<inf>0</inf> states. Such mechanistic understanding based on molecular orbitals, as well as the structure-RTP property relationship study, highlighted design principles embodied by the diketone planar conformer. The fast RTP strategy enables development of organic phosphors with emissions independent of environmental conditions, thereby offering alternatives to precious-metal based phosphors.

DOI： 10.1039/d4sc02841d

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記述言語：日本語   出版者・発行元：光化学協会  

<p>Trivalent lanthanide complexes are attractive candidates for light sources due to their exceptionally pure color emission. Enhancing the photoluminescence intensity through sensitization using ligands with high absorption efficiency is a powerful strategy. However, the microscopic energy transfer mechanisms from organic chromophores to lanthanide ions remain elusive. In this study, we investigated the energy transfer processes in luminescent trivalent europium (Eu³⁺) complexes using time-resolved photoluminescence spectroscopy and transient absorption spectroscopy. Our results successfully elucidated the energy transfer processes from two different ligands, revealing that both energy transfers occur via the triplet excited states of each ligand. Based on these findings, we proposed efficient sensitization using host-to-guest energy transfer in a host-guest film composed of aromatic organic molecules and Eu³⁺ complexes. Our approach resulted in a more than 400-fold enhancement of photoluminescence intensity compared to the intrinsic Eu³⁺ complex.</p>

DOI： 10.60391/koukagaku.55.1_34

CiNii Research

記述言語：英語   出版者・発行元：Faraday Discussions  

In recent years, much attention has been paid to the development of thermally activated delayed fluorescence (TADF) materials with short delayed-fluorescence lifetimes to improve the device performances of OLEDs. In principle, by reducing the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) overlap, while the energy difference between S<inf>1</inf>-T<inf>1</inf> (ΔE<inf>ST</inf>) and activation energy (E<inf>a</inf>) can be reduced, and the reverse intersystem crossing rate constant (k<inf>RISC</inf>) can be accelerated, a decrease in the radiative rate constant happens, necessitating an advanced molecular design. Furthermore, a molecule based on heptazine as a parent skeleton has recently been found to have a peculiar temperature dependence of luminescence decay, suggesting a negative gap (NG) material. In this report, we show that 9-[1,4]benzoxaborino[2,3,4-kl]phenoxaborine-7-yl-1,3,6,8-tetramethyl-9H-carbazole (TMCz-BO), a donor-acceptor linked TADF molecule with a very short delay lifetime of 750 ns, exhibits a peculiar thermal behavior similar to that of NG materials based on the temperature dependence of its luminescence decay in solution.

DOI： 10.1039/d3fd00151b

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Aggregate  

Fluorescence imaging, a key technique in biological research, frequently utilizes fluorogenic probes for precise imaging in living systems. Tetrazine is an effective emission quencher in fluorogenic probe designs, which can be selectively damaged upon bioorthogonal click reactions, leading to considerable emission enhancement. Despite significant efforts to increase the emission enhancement ratio (I<inf>AC</inf>/I<inf>BC</inf>) of tetrazine-functionalized fluorogenic probes, the influence of molecular aggregation on the emission properties has been largely overlooked in these probe designs. In this study, we reveal that an ultrahigh I<inf>AC</inf>/I<inf>BC</inf> can be realized in the aggregate system when tetrazine is paired with aggregation-induced emission (AIE) luminogens. Tetrazine amplifies its quenching efficiency upon aggregation and drastically reduce background emissions. Subsequent click reactions damage tetrazine and trigger significant AIE, leading to considerably enhanced I<inf>AC</inf>/I<inf>BC</inf>. We further showcase the capability of these ultra-fluorogenic systems in selective imaging of multiple organelles in living cells. We term this unique fluorogenicity of AIE luminogen-quencher complexes with amplified dark-bright states as “Matthew effect” in aggregate emission, potentially providing a universal approach to attain ultrahigh I<inf>AC</inf>/I<inf>BC</inf> in diverse fluorogenic systems.

DOI： 10.1002/agt2.499

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DOI： 10.1002/adom.202470007

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DOI： 10.1002/anie.202307093

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Catalysis  

Supramolecular photocatalysts, wherein redox photosensitizer (PS) and catalyst (CAT) molecules are connected to each other, have been extensively studied because of their high photocatalytic activity in both homogeneous and heterogeneous environments compared with the corresponding mixed systems of separated PS and CAT. A supramolecular photocatalyst RuC2PhC2Re, wherein [Ru(diimine)<inf>3</inf>]²⁺ redox PS and fac-[Re(diimine)(CO)<inf>3</inf>{OC(O)OCH<inf>2</inf>CH<inf>2</inf>N(CH<inf>2</inf>CH<inf>2</inf>OH)<inf>2</inf>}] CAT units were spatially separated by a bridging ligand p(-C<inf>2</inf>H<inf>4</inf>)<inf>2</inf>Ph consisting of 8 C-C bonds including a p-phenylene ring, was developed. Although the rate of intramolecular electron transfer of RuC2PhC2Re from one-electron-reduced Ru unit to the Re unit, which is a critical process of photocatalysis proceeding through the bond mechanism, was slower than that of RuC2Re having shorter bridging ligand with an ethylene chain, it could reduce CO<inf>2</inf> to CO with higher durability (TON = 3880) than RuC2Re (TON = 2800). These results clearly suggest that the PS and CAT units can be separated further without lowering photocatalysis of supramolecular photocatalysts because the rate of intramolecular electron transfer is much faster, even in RuC2PhC2Re, than that of the subsequent processes in photocatalytic CO<inf>2</inf> reduction.

DOI： 10.1021/acscatal.3c01407

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

We synthesized a (1-propylpyridinium)<inf>2</inf>[ReN(CN)<inf>4</inf>]-type organic–inorganic hybrid exhibiting water-vapor-induced drastic structural changes of the [ReN(CN)<inf>4</inf>]²⁻ assemblies. Specifically, upon exposure to water vapor, dehydrated nitrido-bridged chains were converted to hydrated cyanido-bridged tetranuclear clusters via rearrangements of large molecular building units in the crystals. These switchable assembly forms display substantially different photo-physical properties, although in both cases the emission is caused by a metal-centered d–d transition. The nitrido-bridged chain exhibited a near-infrared (749 nm) emission, which blue-shifted as the temperature increased, while a visible (561 nm) emission and its red shift was demonstrated by the cyanido-bridged cluster.

DOI： 10.1002/anie.202306853

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記述言語：英語   出版者・発行元：Chemical Communications  

A luminescent three-dimensional coordination polymer (CP) of [Cd^II(pmd){Ag^I(CN)<inf>2</inf>}<inf>2</inf>] (1; pmd = pyrimidine) comprising two different coordination modes of Ag⁺ ions was synthesised herein. 1 exhibited thermochromic luminescence, accompanied by positive thermal elongation of the Ag⋯Ag distance. Moreover, 1 showed a bright phosphorescence with the highest photoluminescence quantum yield (Φ<inf>em</inf>), approximately 60% at room temperature, among previously reported phosphorescent Ag-based CPs or metal-organic frameworks.

DOI： 10.1039/d3cc00179b

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PubMed

記述言語：英語   出版者・発行元：Springer  

Singlet fission (SF), converting a singlet excited state into a spin-correlated triplet-pair state, is an effective way to generate a spin quintet state in organic materials. Although its application to photovoltaics as an exciton multiplier has been extensively studied, the use of its unique spin degree of freedom has been largely unexplored. Here, we demonstrate that the spin polarization of the quintet multiexcitons generated by SF improves the sensitivity of magnetic resonance of water molecules through dynamic nuclear polarization (DNP). We form supramolecular assemblies of a few pentacene chromophores and use SF-born quintet spins to achieve DNP of water-glycerol, the most basic biological matrix, as evidenced by the dependence of nuclear polarization enhancement on magnetic field and microwave power. Our demonstration opens a use of SF as a polarized spin generator in bio-quantum technology.

DOI： 10.1038/s41467-023-36698-4

Web of Science

Scopus

PubMed

CiNii Research

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   出版者・発行元：分子科学会  

<p>As the demands for diverse and complex functionality, the development of photo-functional molecular materials is advanced. In molecules without heavy metals<b>,</b>the electronic excited states can be largely classified into luminescent singlet excited states and non-luminescent triplet excited states. The ability to transition between these two states with vastly different properties through intra/intermolecular electron spin conversion,coupled with the diversity of molecular design, provides a unique advantage in designing photo-functions. Thus, understanding electron spin conversion in molecular systems is fundamentally important from both fundamental science and application perspectives. However, electronic functions are heavily modulated by vibrational degrees of freedom inherent in molecules. Also, study of their photo-functions requires extensive use of time-resolved spectroscopy using ultrafast lasers for capturing the short-lived excited states. Here, several attempts to disentangle the complex molecular excited state dynamics based on ultrafast spectroscopy were introduced. In particular, reverse intersystem crossing and singlet fission are the main topics.</p>

DOI： 10.3175/molsci.17.a0127

CiNii Research

出版者・発行元：Chemical Physics Letters  

The solvent effects were studied on charge-transfer excited states in a donor–acceptor-type luminescent material, phenothiazine-triphenyltriazine, which has two distinct conformers: quasi-coplanar and perpendicular conformers. The solvent dielectric permittivity dependence of the steady-state photoluminescence spectra using solvent mixtures of toluene and tetrahydrofuran (THF) indicated that the two conformers have nearly identical excited-state dipole moments. The time-resolved photoluminescence and transient absorption spectra in toluene and THF showed different solvent dependences for the two conformers. A detailed analysis of these time-resolved spectra revealed solvent-dependent emission processes in the two conformers.

DOI： 10.1016/j.cplett.2022.140155

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Scopus

記述言語：英語   出版者・発行元：Inorganic Chemistry  

Chemical responsivity in materials is essential to build systems with switchable functionalities. However, polarity-switchable materials are still rare because inducing a symmetry breaking of the crystal structure by adsorbing chemical species is difficult. In this study, we demonstrate that a molecular organic-inorganic hybrid crystal of (NEt<inf>4</inf>)<inf>2</inf>[MnN(CN)<inf>4</inf>] (1) undergoes polarity switching induced by water vapor and transforms into a rare example of proton-conducting second-harmonic-generation-active material. Centrosymmetric 1 transforms into noncentrosymmetric polar 1·3H<inf>2</inf>O and 1·MeOH by accommodating water and methanol molecules, respectively. However, only water vapor causes a spontaneous single-crystal-to-single-crystal transition. Moreover, 1·3H<inf>2</inf>O shows proton conduction with 2.3 × 10^-6S/cm at 298 K and a relative humidity of 80%.

DOI： 10.1021/acs.inorgchem.2c02555

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Scopus

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/adom.202101048

記述言語：英語   出版者・発行元：Chemistry A European Journal  

A complex comprising one [Re(CO)<inf>3</inf>]⁺ unit and a phthalocyanine (Pc) ligand (Re<inf>1</inf>Pc) is shown to function as a photo-induced CO-releasing molecule (photoCORM) in the presence of O<inf>2</inf> and a coordinative solvent under irradiation with red light, which can deeply penetrate living tissues. Transient absorption spectroscopic measurements indicate very short excited-state lifetimes and ultrafast intersystem crossing for Re<inf>1</inf>Pc and Re<inf>2</inf>Pc, which contains two [Re(CO)<inf>3</inf>]⁺ units. The excited-state properties are ascribed to efficient spin–orbit coupling and large Franck–Condon factors originating from the complexes’ distorted structures, that is, unsymmetric coordination of [Re(CO)<inf>3</inf>]⁺ unit(s), one of which was confirmed by single-crystal X-ray analysis of a symmetrically substituted Pc with two [Re(CO)<inf>3</inf>]⁺ units. Re<inf>1</inf>Pc represents a promising red-light-driven photoCORM that can be applied in biological environments or therapeutic applications.

DOI： 10.1002/chem.202200716

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Scopus

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Advanced Functional Materials  

The electronic structure and photophysics of the recently designed organic direct singlet harvesting (DSH) molecule are explored, in which donor (D) and acceptor (A) are held at distance by two bridges. One of the bridges is functionalized with fluorene. This structure leads to an ultrasmall singlet–triplet energy gap of ∆E (S<inf>1</inf>−T<inf>1</inf>) ≈ 10 cm⁻¹ (≈1 meV) between the charge transfer states ^1,3CT and shows an energetically close-lying ³ππ* state localized on fluorene. Dielectric constant variation of the environment leads to state crossing of ³ππ* and ^1,3CT near ε = 2.38 (toluene), as confirmed through time-dependent density functional theory (DFT) and state-specific DFT/polarizable continuum model excited-state calculations. Transient absorption (TA) and time-resolved luminescence in the femtosecond to microsecond regimes show rates of intersystem crossing (ISC) and reverse ISC (rISC) of >10⁹ s^–1. Thus, a strictly mono-exponential short-lived photo-luminescence decay (431 ns) is observed, revealing that rISC is no longer the bottleneck responsible for long thermally activated delayed fluorescence. Ultrafast TA displays a time constant of ≈700 fs, representing the relaxation time of DSH and its solvent environment to the relaxed ¹CT state with a molecular dipole moment of ≈40 D. Importantly, OLED devices, emitting sky-blue light and showing high external quantum efficiency of 19%, confirm that singlet and triplet excitons are harvested efficiently.

DOI： 10.1002/adfm.202201772

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie International Edition  

This study reports the facile syntheses of tetra-boron difluoride (tetra-BF<inf>2</inf>) complexes, flag-hinge-like molecules that exhibit intense green-to-orange luminescence in solution and yellow-to-red emission in the solid states. Single-crystal structure analysis and density functional theory calculations suggested a bent structure of this series of compounds. The complexes also exhibited excellent optical properties, with quantum yields reaching 100 % and a large Stokes shift. These properties were attributed to the altered bending angle of the molecule in the S<inf>1</inf> excited state. As the rotational motion was suppressed around the 2,2′-bipyrrole axis, atropisomers with axial chirality were formed, which are optically resolvable into (R) and (S)-enantiomers through a chiral column. The atropisomers thus function as circularly polarized luminescent (CPL) materials, in which the color (green, green-yellow, and yellow) can be varied by controlling the aggregation state. This rational design of multi-BF<inf>2</inf> complexes can potentially realize novel photofunctional materials.

DOI： 10.1002/anie.202204358

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PubMed

出版者・発行元：Journal of Materials Chemistry C  

Novel thermally-activated delayed fluorescence (TADF) materials 2Cz2SB and 2Mi2SB, possessing N-heterocycle and arylsulfonyl groups, were synthesized and their photophysical properties in solution and the solid state were characterized. 2Cz2SB and 2Mi2SB exhibit typical TADF characteristics and aggregation-induced emission or crystallization-induced emission behaviour. Specifically, they display a blueshift of photoluminescence wavelength and an increase in photoluminescence quantum yield (Φ<inf>PL</inf>) in the aggregate and solid states, owing to suppression of thermal deactivation. The results of time-resolved IR analysis suggest that aggregate and solid state promoted suppression of geometrical changes in the excited state causes the observed increases in Φ<inf>PL</inf>

DOI： 10.1039/d1tc05196b

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Scopus

出版者・発行元：Bulletin of the Chemical Society of Japan  

We investigated the correlation between the photophysical properties and detailed excited-state characteristics of a multiple-resonance-type thermally activated delayed fluorescence (TADF) molecule, DABNA-1, using time-resolved infrared vibrational spectroscopy. By comparing the distinctive vibrational spectra in the fingerprint region (10001700 cm¹¹) to the simulated spectra, we found the optimal calculation conditions for density functional theory calculations to retrieve the vibrational spectra. Based on the calculations, the excited-state geometries and molecular orbitals in the lowest excited singlet (S<inf>1</inf>) and triplet (T<inf>1</inf>) states, as well as the ground state (S<inf>0</inf>), were determined. Consequently, we revealed that the similarity between the potential surfaces of T<inf>1</inf> and S<inf>0</inf> suppressed non-radiative decay and improved the high fluorescence quantum yield via TADF. Furthermore, we calculated the spin-orbit coupling matrix elements (SOCMEs) considering the experimentally confirmed geometries, and revealed that twisting of the main skeleton increases the SOCMEs.

DOI： 10.1246/bcsj.20210403

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Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Materials Chemistry C  

Efficient triplet-triplet annihilation-based photon upconversion (TTA-UC) from visible to UV light without using heavy metals is still a challenging task. Here we achieve a record-high TTA-UC efficiency of 20.3% among 100% maximum by employing a ketocoumarin derivative as a triplet sensitizer, which shows strong visible absorption, weak UV absorption, and efficient intersystem crossing.

DOI： 10.1039/D1TC05526G

Web of Science

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Advanced Optical Materials  

In organic microcavities, a macroscopic condensate of exciton-polaritons can be formed at high-exciton polariton densities. The threshold for forming this condensate is proportional to the relaxation rate from initially excited excitons to these polaritons and the lifetime of the lowest energy polariton states. Although the influence of the lower polariton (LP) lifetime on the threshold has been studied, the relationship between the polariton relaxation rate and the threshold has not been fully explored. In this study, a room-temperature polariton condensate is demonstrated at a threshold pump fluence of 9.7 ± 0.1 µJ cm⁻², in a microcavity containing 4,4″-bis((E)-4-(3,6-bis(2-ethylhexyl)-(9H-carbazol-9-yl))styryl)-1,1″-biphenyl (BSBCz-EH). By using a semiclassical model to describe the polariton kinetics, it is revealed that this low threshold results from the rapid relaxation rate from the dark exciton reservoir to the set of the LP states forming the condensate, with an effective rate W<inf>ep</inf> ≈ 2.0 × 10⁻⁵ cm³ s⁻¹. These results show that accelerating polariton relaxation is possible and is an important factor for realizing low-threshold polariton condensates.

DOI： 10.1002/adom.202102034

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Scopus

その他リンク： https://doi.org/10.1002/adom.202102034

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.inorgchem.1c00146

その他リンク： https://doi.org/10.1021/acs.inorgchem.1c00146

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/D1SC02213J

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/d1sc02213j

その他リンク： https://doi.org/10.1039/d1sc02213j

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.inorgchem.1c00702

その他リンク： https://doi.org/10.1021/acs.inorgchem.1c00702

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jpca.0c09337

その他リンク： https://doi.org/10.1021/acs.jpca.0c09337

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/d0cc05462c

その他リンク： http://dx.doi.org/10.1039/d0cc05462c

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/C9CC09062B

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsnano.9b03060

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1038/s41467-018-07972-7 |

その他リンク： https://www.nature.com/articles/s41467-018-07972-7

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/adma.201707312

その他リンク： https://onlinelibrary.wiley.com/doi/full/10.1002/adma.201707312

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

その他リンク： https://www.jove.com/video/57612/novel-techniques-for-observing-structural-dynamics-photoresponsive

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jpcc.8b00476

その他リンク： https://pubs.acs.org/doi/abs/10.1021/acs.jpcc.8b00476

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acsenergylett.7b00717

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1126/sciadv.1602388

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/jacs.6b13089

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/adma.201603072

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acscentsci.6b00063

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jpcc.5b12686

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.7567/JJAP.52.062401

その他リンク： https://iopscience.iop.org/article/10.7567/JJAP.52.062401

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/978-3-319-13242-6_52

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c3cp54157f

開催年月日： 2023年3月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：online   国名：日本国  

開催年月日： 2022年12月

記述言語：日本語  

開催地：オンライン   国名：日本国  

開催年月日： 2022年9月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Fukuoka   国名：日本国  

開催年月日： 2022年8月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Fukuoka   国名：日本国  

開催年月日： 2022年7月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Glasgow   国名：グレートブリテン・北アイルランド連合王国(英国)  

開催年月日： 2022年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2022年6月

記述言語：日本語  

国名：日本国  

開催年月日： 2022年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2020年1月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Shanghai, China   国名：日本国  

その他リンク： http://acup2020.htcis.net/

開催年月日： 2019年12月

記述言語：日本語   会議種別：公開講演，セミナー，チュートリアル，講習，講義等  

開催地：東京   国名：日本国  

開催年月日： 2019年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：札幌   国名：日本国  

新しい社会的ニーズにこたえるため、分子性材料の開発。有効利用重要性はますます増しているが、それらを支える基盤研究が必ずしも十分でない。特に光が絡んだ現象は超高速分光を駆使した実時間解析が強力である。ここでは、発表者が過去に携わってきた最先端の知見を応用物理学会の聴衆に向けて発信した。

開催年月日： 2019年7月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Wako, Saitama   国名：日本国  

その他リンク： https://cems.riken.jp/topicalmeeting/orgphotoelec2019/

開催年月日： 2019年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：Ritsumeikan University   国名：日本国  

開催年月日： 2019年1月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Brisbane   国名：オーストラリア連邦  

開催年月日： 2018年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：名古屋   国名：日本国  

開催年月日： 2018年7月

記述言語：日本語   会議種別：口頭発表（招待・特別）  

開催地：福岡   国名：日本国  

開催年月日： 2018年7月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：札幌   国名：日本国  

オプトエレクトロニクスで重要となっている新規材料鉛ハライドペロブスカイト半導体について、独自に開発した時間分解で構造ダイナミクスに関する情報を得ることができる時間分解カー効果分光を適用することで物性の理解を提案した発表。特に誘電関数の特異性に注目して物性を整理した点が特徴である。

開催年月日： 2025年1月

開催年月日： 2024年12月

開催年月日： 2024年10月

開催年月日： 2024年9月

開催年月日： 2024年7月

開催年月日： 2024年7月

開催年月日： 2024年6月

開催年月日： 2023年12月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：京都   国名：日本国  

開催年月日： 2023年10月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京   国名：日本国  

開催年月日： 2023年9月

記述言語：日本語  

開催地：広島   国名：日本国  

開催年月日： 2023年8月 - 2023年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：Fukuoka   国名：日本国  

開催年月日： 2023年8月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：山梨大学   国名：日本国  

開催年月日： 2023年7月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Sapporo   国名：日本国  

開催年月日： 2023年5月

記述言語：英語  

開催地：福岡   国名：日本国  

開催年月日： 2023年5月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2023年3月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2023年1月

記述言語：日本語  

開催地：福岡   国名：日本国  

開催年月日： 2022年12月

記述言語：日本語  

開催地：東京   国名：日本国  

開催年月日： 2022年12月

記述言語：英語  

開催地：online   国名：日本国  

開催年月日： 2022年11月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：online   国名：日本国  

開催年月日： 2022年9月

記述言語：日本語  

開催地：横浜   国名：日本国  

開催年月日： 2022年9月

記述言語：日本語  

国名：日本国  

開催年月日： 2022年8月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2022年7月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2022年7月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：online   国名：日本国  

開催年月日： 2022年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2022年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2020年12月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2020年12月

記述言語：日本語  

開催地：オンライン   国名：日本国  

開催年月日： 2020年11月

記述言語：日本語  

開催地：オンライン   国名：日本国  

開催年月日： 2020年9月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2020年6月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2020年1月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：九州大学   国名：日本国  

開催年月日： 2019年12月

記述言語：日本語  

開催地：和光市   国名：日本国  

開催年月日： 2019年8月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：富山   国名：日本国  

開催年月日： 2019年7月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：九重、大分県   国名：日本国  

その他リンク： http://www.scc.kyushu-u.ac.jp/Kouzou/kuju2019/index.html

開催年月日： 2019年6月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Qiandao Lake   国名：中華人民共和国  

開催年月日： 2019年3月

記述言語：日本語  

開催地：九州大学   国名：日本国  

開催年月日： 2019年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：千葉大学   国名：日本国  

開催年月日： 2019年2月 - 2019年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：大阪大学　産業科学研究所   国名：日本国  

開催年月日： 2018年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：福岡   国名：日本国  

開催年月日： 2018年9月

記述言語：日本語  

開催地：関西学院大学   国名：日本国  

開催年月日： 2018年6月

記述言語：日本語  

国名：日本国  

開催年月日： 2018年6月

記述言語：日本語  

国名：日本国  

開催年月日： 2017年11月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Boston, MA   国名：アメリカ合衆国  

開催年月日： 2017年8月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：San Diego, CA   国名：アメリカ合衆国  

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

Photofunctional materials based on rare earth ions have attracted much attention because they demonstrate unique properties that cannot be achieved by other materials. However, the microscopic mechanisms that lead to the unique functions have not necessarily been clarified, which is a challenge for further material design. Although it is important to understand the excited state/carrier dynamics that occur in the material after light absorption, it is not easy to capture the elementary processes experimentally because the processes after photoexcitation proceed on very fast time scales such as pico- or nano-seconds. We are tackling these challenges by successfully applying ultrafast time-resolved spectroscopy with a home-built instrument constructed using a femtosecond ultrashort pulsed laser (time duration ~100 fs). In this talk, we will introduce some of the issues we have been working on in our laboratory, such as (1) ultrafast photocarrier trapping processes in inorganic materials containing Eu(II) ions that exhibit mechano-luminescence properties, and (2) ultrafast spectroscopic approaches to the intramolecular energy transfer of lanthanide trivalent complexes for highly luminescent materials.

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

記述言語：英語  

種別：大会・シンポジウム等 

参加者数：2,500

種別：大会・シンポジウム等 

参加者数：2,700

種別：査読等 

外国語雑誌　査読論文数：7

種別：査読等 

外国語雑誌　査読論文数：3

種別：査読等 

外国語雑誌　査読論文数：2

種別：査読等 

外国語雑誌　査読論文数：2

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：その他

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

バーチャルシンポジウム形式で最先端の科学を誰でmおいつでも聞ける形で発信し、緊急事態下での新たな学びの場を提供した。企画うから担当し、二週間の準備期間で日程・プログラムの確定と当日のファシリテータまで遂行した。

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：セミナー・ワークショップ

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：講演会

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