Article
Chemistry, Physical
Athira K. Jeevan, Karical R. Gopidas
Summary: In water, pyrene linked to cyclodextrin molecules and methylviologen linked to adamantane groups self-assembled to form toroidal nanostructures. Efficient electron transfer between pyrene and methylviologen resulted in fast quenching of pyrene fluorescence and the formation of radical ion products, which undergo further reactions within the close-packed chromophores in the assembly.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Multidisciplinary
Liang-Chun Lin, Tanner Smith, Qianxiang Ai, Brandon K. Rugg, Chad Risko, John E. Anthony, Niels H. Damrauer, Justin C. Johnson
Summary: In this study, a pyrene-bridged parallel tetracene dimer (TPT) with optimized interchromophore coupling strength was synthesized. The long-lived and strongly spin-polarized multiexciton quintet state, (TT)-T-5, was observed through transient absorption and electron paramagnetic resonance spectroscopy. The lifetime of (TT)-T-5 was estimated to be >35 μs, with a dephasing time (T-2) of 726 ns at 10 K for the corresponding qubit. The experimental results support recent theoretical models.
Article
Chemistry, Inorganic & Nuclear
Franciska S. Gogesch, Lea Bauer, Florian D. Vollstaedt, Michael Linseis, Laura Senft, Ivana Ivanovic-Burmazovic, Rainer F. Winter
Summary: Through the study of complexes, it is found that complexes with π-conjugated linkers can effectively decouple electrons, thus stabilizing fluorescence emission.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Taylor O. Hope, Tamara Reyes-Robles, Keun Ah Ryu, Steven Mauries, Nicole Removski, Jacinthe Maisonneuve, Rob C. Oslund, Olugbeminiyi O. Fadeyi, Mathieu Frenette
Summary: We investigated the photocatalytic activation of phenols for tyrosine labelling using flavin-based photocatalysts, and found that the initial covalent binding between phenols and tyrosine is not radical addition, but radical-radical recombination. This proposed mechanism may also explain the mechanism of other reported tyrosine-tagging approaches. Competitive kinetics experiments showed the generation of phenoxyl radicals through multiple pathways involving the excited riboflavin-photocatalyst or singlet oxygen, increasing the likelihood of radical-radical recombination.
Article
Chemistry, Physical
Christopher Schad, Edurne Avellanal-Zaballa, Esther Rebollar, Cesar Ray, Eduardo Duque-Redondo, Florencio Moreno, Beatriz L. Maroto, Jorge Banuelos, Inmaculada Garcia-Moreno, Santiago De la Moya
Summary: We proposed a new approach for achieving triplet-triplet annihilation-assisted photon upconversion by the rational design of an all-organic molecular assembly. This design takes advantage of the synthetic accessibility and chemical versatility of COO-BODIPY scaffold. Laser-induced photophysical characterization and computational simulations were used to understand and control the energy transfer efficiency between triplet states. Theoretical simulations also demonstrated the importance of the new photoactivable chromophoric design for enhancing photon upconversion.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Engineering, Environmental
Jialiang Liang, Jingke Wu, Pengfei Gan, Yudan Liu, Peng Zhen, Yunyi Li, Zhiwei Zhao, Wen Liu, Meiping Tong
Summary: This study investigates the dephosphorization of dimethoate (DMT), a representative organophosphorus pesticide, using a vacuum ultraviolet system. It finds that non-radical processes, such as photoexcitation and singlet oxygen atoms (O(1D)), have a significant effect on DMT dephosphorization. The study highlights the significant contribution of non-radical pathways in DMT dephosphorization by VUV.
Article
Chemistry, Multidisciplinary
Pengkun Su, Heyuan Liu, Li Shen, Jun Zhou, Weijie Wang, Shanshan Liu, Xinyu Nie, Zhi Li, Zhaobin Liu, Yanli Chen, Xiyou Li
Summary: In this study, three dimers with different orientations were synthesized to control the electronic coupling strength and symmetry breaking charge separation (SB-CS) process. The o-dimer could achieve fast SB-CS in weakly polar solvents, while the m-dimer only showed slow SB-CS process in polar solvents. These results are of great importance for developing novel SB-CS materials for practical applications.
MATERIALS CHEMISTRY FRONTIERS
(2022)
Article
Multidisciplinary Sciences
Yi Cui, Lu Liu, Huihang Lin, Kai-Hsin Wu, Wenshan Hong, Xuefei Liu, Cong Li, Ze Hu, Ning Xi, Shiliang Li, Rong Yu, Anders W. Sandvik, Weiqiang Yu
Summary: By using high-pressure 11B nuclear magnetic resonance measurements, we have observed a magnetic field-induced plaquette singlet to antiferromagnetic transition in the quantum magnet SrCu2(BO3)2. The first-order signatures of the transition weaken with increasing pressure, and quantum critical scaling is observed at the highest pressure. These findings provide an experimental platform for investigating the deconfined quantum critical point.
Article
Chemistry, Multidisciplinary
Yilin Chen, Jiancheng Li, Yiling Zhao, Li Zhang, Gengwen Tan, Hongping Zhu, Herbert W. Roesky
Summary: In this study, compound 2 undergoes charge transfer reactions with various reagents, leading to the formation of stable radical cation and dication species of the 1,4-disilabenzene. Additionally, compound 2 also undergoes oxidative addition reactions with group 16 elements such as O, S, and Se.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Engineering, Environmental
Lingwei Gao, Yang Guo, Juhong Zhan, Gang Yu, Yujue Wang
Summary: This study evaluated the effects of various quenchers on the mechanism of a cobalt mediated peroxymonosulfate (Co(II)/PMS) process and found that these quenchers not only quench target reactive species but also cause interference effects. Therefore, caution should be exercised when applying the quenching method to investigate the mechanism of the persulfate-based process.
Article
Chemistry, Multidisciplinary
Mithilesh Kumar Nayak, Pallavi Sarkar, Benedict J. Elvers, Sakshi Mehta, Fangyuan Zhang, Nicolas Chrysochos, Ivo Krummenacher, Thangavel Vijayakanth, Ramakirushnan Suriya Narayanan, Ramapada Dolai, Biswarup Roy, Vishal Malik, Hemant Rawat, Abhishake Mondal, Ramamoorthy Boomishankar, Swapan K. Pati, Holger Braunschweig, Carola Schulzke, Prince Ravat, Anukul Jana
Summary: In this study, a thermally stable dicationic diradical compound was synthesized and confirmed by EPR spectroscopy. The presence of the trans-1,4-cyclohexylene bridge was found to be essential for the successful isolation of this compound.
Article
Chemistry, Analytical
Virendra Kumar, Pawan Kumar, Paramjit Kaur, Kamaljit Singh
Summary: A new fluorescent molecular probe, DPY, sensitive to hydrazine and protonation, exhibits ratiometric fluorescent emission changes and different fluorescence properties in various environments. This probe shows strong emission in solution and solid state due to intramolecular charge-transfer, and its fluorescence can be quenched or revived with exposure to different chemicals.
ANALYTICA CHIMICA ACTA
(2021)
Article
Chemistry, Multidisciplinary
Yunjun Cao, Joel Mieres-Perez, Karsten Lucht, Iris Ulrich, Paul Schweer, Elsa Sanchez-Garcia, Karina Morgenstern, Wolfram Sander
Summary: A novel surface-confined C-C coupling reaction involving two carbene molecules and a water molecule was studied by scanning tunneling microscopy. In the presence of water, carbene fluorenylidene was generated from diazofluorene on a silver surface, while in the absence of water, fluorenylidene formed a surface metal carbene. Water molecules in direct contact with fluorenylidene protonated the carbene before it could bind to the surface, whereas the surface metal carbene did not react with water. The final step in this reaction sequence involved the reaction of the fluorenyl radical with a remaining fluorenylidene molecule or with diazofluorene to produce the C-C coupling product. Both water and the metal surface were essential for the consecutive proton and electron transfer followed by C-C coupling. This C-C coupling reaction is unprecedented in solution chemistry.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Kaixuan Wang, Xing Kang, Chen Yuan, Xing Han, Yan Liu, Yong Cui
Summary: The study demonstrates that the photocatalytic performance of COFs is heavily dependent on their structural dimensionality, with 2D-PN COFs showing higher catalytic activity and improved synthesis performance compared to 3D-PN COFs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Jun-Ying Feng, Yuan-Pern Lee, Henryk A. Witek, Takayuki Ebata
Summary: The structures and reactions of pyridine cluster cations generated at specific ionization energy were investigated using infrared action spectroscopy. Proton and deuteron migration during formation and dissociation of the cluster cations were observed, with reactions involving alpha-distonic cation intermediates and proton migration pathways, respectively. Infrared spectra indicated that the clusters consist of a core covalently bound with additional pyridines via hydrogen bonds and/or weak dispersive interactions.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Tsuyoshi Murata, Noriaki Asakura, Ryotaro Tsuji, Yuki Kanzaki, Kazunobu Sato, Takeji Takui, Yasushi Morita
Summary: A new stable organic compound was synthesized, and porous organosiloxanes were prepared through the condensation of silyl groups. The compound exhibited unique characteristics in both solution and solid states. Additionally, the organosiloxanes demonstrated reversible redox ability.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Inorganic & Nuclear
Ryu Tanimoto, Tomoyuki Wada, Keiji Okada, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Shuichi Suzuki, Takeshi Naota, Masatoshi Kozaki
Summary: This study investigates the magnetic behavior of a gadolinium(III) complex at different temperatures and finds that the magnetic susceptibility changes with temperature, which can be explained by the structural change of the ligand.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Koki Horii, Ryohei Kishi, Masayoshi Nakano, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Akihito Konishi, Makoto Yasuda
Summary: Bis-periazulene and its derivatives exhibit unique electronic structures and energy states, providing potential applications in extended π-conjugated systems.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Organic
Tsuyoshi Murata, Kenta Yoshida, Shuichi Suzuki, Akira Ueda, Shinsuke Nishida, Junya Kawai, Kozo Fukui, Kazuhiro Nakasuji, Yasushi Morita
Summary: Tri-tert-butylated 4,7-dihydroxyphenalenone derivative was synthesized from a corresponding 4,9-dimethoxyphenalenone derivative through regioselective deoxygenation/oxygenation. The derivative exhibited chromic behavior accompanied by protonation and deprotonation, resulting in monocation and dianion species, respectively. The C-3 symmetric electronic structures of these species were elucidated using experimental and theoretical methods.
Article
Chemistry, Multidisciplinary
Junya Adachi, Masaya Naito, Sho Sugiura, Ngoc Ha-Thu Le, Shoma Nishimura, Shufang Huang, Shuichi Suzuki, Soichiro Kawamorita, Naruyoshi Komiya, Jonathan P. Hill, Katsuhiko Ariga, Takeshi Naota, Taizo Mori
Summary: This study aims to establish the importance of molecular design for the formation of monolayers at an air-water interface using the concept of coordination amphiphile based on ligand characteristics and molecular topology. The results show that ligand characteristics and molecular topology significantly influence interfacial activity, and appropriate hydrophilicity and hydrogen bonding are key factors for monolayer formation.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2022)
Article
Physics, Atomic, Molecular & Chemical
Isao Suetake, Kazunobu Sato, Tomoaki Sugishita, Yuichi Mishima, Toshiki Takei, Toshimichi Fujiwara, Risa Mutoh, Akira Shinohara, Takeji Takui, Makoto Miyata, Hironobu Hojo, Toshiaki Arata
Summary: Heterochromatin protein 1 (HP1) is an epigenetic reader with two conserved domains, the chromoshadow domain (CSD) and chromodomain (CD). The hinge region (HR) connects the CD and CSD. The N- and C-tails as well as the HR are estimated to be disordered. EPR spectra showed site-specific slower dynamics in the disordered regions, with the HR being influenced by the N-tail and the C-terminal region of HR interacting with the C-tail. Surprisingly, DNA did not affect the spectra, but restricted CD and CSD in HP1 alpha.
APPLIED MAGNETIC RESONANCE
(2023)
Article
Physics, Atomic, Molecular & Chemical
Kazunobu Sato, Rei Hirao, Satoru Yamamoto, Konstantin L. Ivanov, Takeji Takui
Summary: This article presents methods for optimizing frequency sweeps to achieve fast adiabatic inversion in ESR spectroscopy. The optimization is performed either by exploiting constant adiabaticity chirps or using the gradient ascent pulse engineering (GRAPE) method, which evaluates the & UDelta;(t) profiles to minimize the chirp duration. Arbitrary waveform generator-based ESR (AWG-ESR) allows for the application of versatile MW-shaped pulses and control of the spin system dynamics. Spin dynamics for spin inversion by the shaped pulses were observed. Comparison of different frequency sweeps indicates a significant reduction in the duration of adiabatic sweeps for both homogeneous and inhomogeneously broadened ESR signals.
APPLIED MAGNETIC RESONANCE
(2023)
Editorial Material
Physics, Atomic, Molecular & Chemical
Kazunobu Sato, Elena Bagryanskaya, Marco Affronte, Stephen Hill
APPLIED MAGNETIC RESONANCE
(2023)
Article
Chemistry, Multidisciplinary
Kaho Harada, Chika Hasegawa, Taisuke Matsumoto, Hiroki Sugishita, Chitoshi Kitamura, Shuhei Higashibayashi, Masashi Hasegawa, Shuichi Suzuki, Shin-ichiro Kato
Summary: A structurally constrained, double-helical S,C-bridged tetraphenyl-para-phenylenediamine (TPPD) has been synthesized. The stable radical cation of the S,C-bridged TPPD was generated by chemical oxidation, and the electron spin was found to be delocalized over the entire pi-conjugated framework. The excellent conformational stability of the neutral molecule facilitated the separation of its enantiomers.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Shohei Koyama, Kazunobu Sato, Masahiro Yamashita, Ryota Sakamoto, Hiroaki Iguchi
Summary: The study investigates the magnetic relaxation of BTI-xy radical anions without pi-stacking interaction, which leads to slow magnetization relaxation reported for the first time in organic radicals. The relaxation times in a solution state highlight the significance of spin interaction.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Keiga Toshima, Tetsu Sato, Yoji Horii, Kazunobu Sato, Kenji Sugisaki, B. K. Breedlove, Shinya Takaishi, Zhao-Yang Li, Masahiro Yamashita
Summary: This study reports the slow magnetic relaxation behavior and T-2 values of three low-spin Ni(III) based complexes, suggesting their potential as molecule-based spin qubits under magnetically diluted conditions.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Akihiro Shimizu, Masaaki Hayashida, Yuta Ochi, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Ryo Shintani
Summary: A zwitterionic open-shell singlet diradical composed of electron-donating anion and electron-accepting cation was synthesized and showed near-infrared absorption. The diradical has a small energy gap between the ground singlet and thermally-excited triplet states (Delta E-ST), which can be changed by solvents.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Shuichi Suzuki, Toshihiro Sakai, Sota Takagi, Takeshi Naota
Summary: The light-transmissive properties of a solidstate tetrathiafulvalene radical cation bis(trifluoromethanesulfonyl)imide (1-C-5(center dot+) center dot NTf2-) can be instantly changed in the short-wave infrared (SWIR) region upon exposure to solvent vapor or the application of mechanostress at room temperature. The changes are characterized by significant variations in absorption in the SWIR region, which can be reversed spontaneously and promptly upon cessation of vapor stimulation or mechanical stress. These changes in transparency to SWIR light are caused by structural transformations of the radical cations, from columnar to isolated pi-dimer structures under different conditions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Shinobu Arikawa, Akihiro Shimizu, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Hikaru Sotome, Hiroshi Miyasaka, Masahito Murai, Shigehiro Yamaguchi, Ryo Shintani
Summary: A kinetically-stabilized nitrogen-doped triangulene cation derivative with a triplet ground state that exhibits near-infrared emission has been synthesized and isolated. The triplet ground state with a large singlet-triplet energy gap was experimentally confirmed by magnetic measurements. The nitrogen-doped triangulene cation derivative is highly stable even in solution under air and exhibits near-infrared absorption and emission due to the broken alternancy symmetry of triangulene.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Shuichi Suzuki, Ruifeng Shu, Daisuke Shiomi, Takeshi Naota
Summary: A liquescent nickel(III) complex with a bis(methoxyethyl)imidazolium cation exhibits three-stage thermochromic modulation in the SWIR region. The transparency/absorption shifts to shorter wavelengths upon heating, and a blue-shift of absorption occurs in the liquid phase at higher temperatures. The changes can be attributed to the dissociation of the associated structures during phase transitions and the shift of dimer-monomer equilibrium in the liquid state.
