Article
Chemistry, Physical
Kaori Fujii, Tomoaki Yagi, Hiroshi Nakano, Hirofumi Sato, Yoshifumi Kimura
Summary: The recombination dynamics of geminate PAPT radicals produced in ionic liquids were investigated using transient absorption spectroscopy, showing that the recombination yields and dynamics were virtually independent of the cation species. A theoretical analysis model incorporating a square well potential was used to simulate the experimentally obtained time profiles and final yield successfully. The optimized parameters for the fit, including the mutual diffusion coefficient, cage radius, and well depth, were discussed in terms of conventional diffusion theory and potential mean force estimated from molecular dynamics simulation.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Kyohei Nakano, Yumiko Kaji, Keisuke Tajima
Summary: This study evaluates the impact of electric field-dependent charge generation in organic photovoltaics with different structures and finds that the electric field dependence is more pronounced in planar heterojunction structures. The insufficient energy difference and the relative molecular orientation at the donor/acceptor interfaces are important factors in the charge generation process.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Physical
Thomas P. Fay, Lachlan P. Lindoy, David E. Manolopoulos
Summary: The stochastic Schrodinger equation (SSE) is shown to be an ideal method for simulating quantum mechanical spin dynamics of radical pairs, providing an efficient way to handle electron spin relaxation effects and compute experimental observables. Comparative studies with other methods, such as the Lindblad equation, demonstrate the superior efficiency and broader applicability of the SSE approach. The accuracy of the SSE results in assessing theories combining spin relaxation and dynamics for radical pairs with multiple nuclear spins is also highlighted, along with a detailed analysis of trace sampling efficiency using SU(N) coherent states.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Meltem Tolunay, Ieva Liepuoniute, Mariya Vyushkova, Barbara A. Jones
Summary: This study utilizes quantum computers to simulate the Hamiltonian evolution and thermal relaxation of two radical pair systems undergoing the quantum beats phenomenon. By leveraging the inherent qubit noise, we are able to simulate the noisy quantum beats in the two radical pair systems better than with any classical approximation or quantum simulator. Near-term quantum computers can match the experimental data throughout its time evolution, showcasing their unique suitability and future promise in simulating open quantum systems in chemistry.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Condensed Matter
M. E. Raikh
Summary: The origin of magnetoresistance in bipolar organic materials is attributed to the influence of magnetic field on the recombination dynamics of localized electron-hole pairs. Recombination between the S and T0 states is influenced by the random hyperfine field. When the recombination time from S is shorter than the beating period, a weak resonant ac drive coupling T0 to T+ and T- significantly affects the recombination dynamics and current, resulting in a maximum current at a certain drive amplitude.
SOLID STATE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Victor A. Bagryansky, Anatoly R. Melnikov, Yuri N. Molin, Vsevolod I. Borovkov
Summary: This study investigates the effects of dipole-dipole interaction on the kinetics of spin-selective reactions using a rigorous kinetic model. The results show that increasing the exchange coupling and reaction rate constants can slow down spin transitions and reaction rates. Additionally, the presence of irreversible reactions in the doublet states affects the evolution of the non-reactive quartet subsystem.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Yina Zheng, Yao Wu, Zhihao Chen, Xinxin Xia, Yawen Li, Qiang Wu, Yuze Lin, Xinhui Lu, Xiaotao Hao, Jie Min
Summary: The device performance of polymer solar cells (PSCs) is closely related to the microstructure of the active layer. Using a conjugated-block copolymer (CBC) as the active layer, we compared its photovoltaic performance with that of the bulk heterojunction (BHJ) system. Although both systems show high device efficiencies, the contributions of relevant photovoltaic parameters are different. Our work demonstrates that CBC materials are promising for reducing the efficiency-stability gap of PSCs, compared to BHJ systems.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Physics, Atomic, Molecular & Chemical
Serguei V. Feskov, Anatoly I. Ivanov
Summary: This study investigates the kinetics of radical-ion pairs formed by photoinduced electron transfer in solution and the triplet and singlet products of their recombination through numerical simulation. The research shows significant differences in charge recombination between singlet and triplet RIPs, with a portion of singlet RIPs undergoing distant recombination. The effect of a strong magnetic field on the triplet charge recombination product yield is also studied, with a decrease in the time-dependent magnetic field effect observed for HFI-induced coherent spin transitions.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Chemistry, Multidisciplinary
Weigang Zhu, Guoping Li, Subhrangsu Mukherjee, Natalia E. E. Powers-Riggs, Leighton O. O. Jones, Eliot Gann, R. Joseph Kline, Andrew Herzing, Jenna L. L. Logsdon, Lucas Flagg, Charlotte L. L. Stern, Ryan M. M. Young, Kevin L. L. Kohlstedt, George C. C. Schatz, Dean M. M. DeLongchamp, Michael R. R. Wasielewski, Ferdinand S. S. Melkonyan, Antonio Facchetti, Tobin J. J. Marks
Summary: Recent studies have shown that nonfullerene acceptors (NFAs) can achieve higher power conversion efficiencies (PCEs) compared to traditional fullerenes in polymer solar cells (PSCs). Understanding the relationship between film morphology, charge carrier dynamics, and photovoltaic performance is crucial for improving materials design and device engineering. Optimization of the incorporation of a fullerene, PC71BM, in a binary blend system can enhance PCE by increasing the charge carrier mobilities and reducing recombination. However, excessive PC71BM can lead to undesirable morphology changes and decreased performance.
ENERGY & ENVIRONMENTAL SCIENCE
(2023)
Article
Mathematics
Ilse Fischer, Florian Schreier-Aigner
Summary: The explicit bijection between alternating sign matrices (ASMs) and descending plane partitions (DPPs) has been an unsolved problem for about 40 years, but quadruples of statistics on ASMs and DPPs with the same joint distribution have been identified. We introduce extensions of ASMs and DPPs along with additional statistics on each extension, and prove that the two families of statistics have the same joint distribution. The equinumerosity of ASMs and DPPs is obtained as a consequence by considering the (-1)-enumerations of these extended objects with respect to one pair of the n + 3 pairs of statistics. The involvement of signs and the necessity of these extensions may provide insights into the obstacles of finding an explicit bijection between ASMs and DPPs. A multivariate generalization of the operator formula for the number of monotone triangles is an important tool in our proof, which generalizes Schur functions.
ADVANCES IN MATHEMATICS
(2023)
Article
Chemistry, Physical
Marius-Andrei Codescu, Moritz Weiss, Martin Brehm, Oleg Kornilov, Daniel Sebastiani, Erik T. J. Nibbering
Summary: Bifunctional or amphoteric photoacids with donor and acceptor properties are useful tools for analyzing proton transfer reactions, and the addition of a formate base can alter the reaction pathways of 7-hydroxyquinoline. By probing the reaction dynamics and comparing transient IR spectra, it was found that tight and loose 7HQ-formate reaction pairs play distinct roles in facilitating net proton transfer along a proton relay pathway.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Physics, Multidisciplinary
Alexander B. Doktorov
Summary: This study examines the recombination yield and the stationary chemically induced dynamic electron spin polarization (CIDEP) in high magnetic fields based on the generalized gyroscopic model of electron spin evolution of radical pair available in the literature. It is found that the longitudinal spin relaxation essentially influences the effective radius of dephasing induced by nonlocal exchange interaction of the radicals.
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Chemistry, Multidisciplinary
Yuying Li, Junle Zhang, Yaxuan Shi, Yuancheng Zhang, Ge Shi, Xiaomeng Zhang, Zhe Cui, Peng Fu, Minying Liu, Xiaoguang Qiao, Yanjie He, Yudong Wang, Haitao Zhao, Wenjie Zhang, Xinchang Pang
Summary: A robust synthesis strategy was proposed in this study to improve the dispersity and interface compatibility of upconversion nanoparticles (UCNPs) and polymethyl methacrylate (PMMA), forming UCNP@PMMA core@shell nanocomposites. These nanocomposites showed high transparency and strong upconversion photoluminescence properties, providing great opportunities for applications in 3D display and optoelectronic fields. The strategy could also be applied to fabricate other functional transparent polymer nanocomposites with uniformly dispersed inorganic nanoparticles.
Article
Psychology, Applied
Huiwen Lian, Jie (Kassie) Li, Jingzhou Pan, Chenduo Du, Qinglin Zhao
Summary: This study develops a model to distinguish the independent and joint effects of positive and negative workplace gossip on the status of gossipers. The findings suggest that positive gossip increases gossiper status by clarifying organizational norms, while negative gossip has both norm clarification and norm violation effects. Positive gossip weakens the norm-violation effects of negative gossip on gossiper status, and each type of gossip replaces the norm clarification effects of the other type of gossip on gossiper status.
JOURNAL OF APPLIED PSYCHOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Alexander B. Doktorov, Nikita N. Lukzen
Summary: Based on the differential Encounter theory, closed kinetic equations were obtained to describe the temporal change in the concentration of free radicals recombining at encounters in liquid dilute solutions. The recombination process is spin-selective and influenced by various spin interactions. An unambiguous relationship has been established between the bulk recombination rate constant and the recombination yields of the corresponding singlet and triplet states.
JOURNAL OF MATHEMATICAL CHEMISTRY
(2023)
Review
Physics, Atomic, Molecular & Chemical
Joerg Matysik, Yonghong Ding, Yunmi Kim, Patrick Kurle, Alexandra Yurkovskaya, Konstantin Ivanov, A. Alia
Summary: Photo-CIDNP is a phenomenon of nuclear polarization created by the spin-chemical evolution of spin-correlated radical pairs, which can occur in gases, liquids, and solids. The solid-state photo-CIDNP effect observed under magic-angle spinning has led to the development of photo-CIDNP MAS NMR as an analytical method.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Physics, Atomic, Molecular & Chemical
Konstantin L. Ivanov, Alexandra V. Yurkovskya, Natalya N. Fishman, Aleksey S. Kiryutin, Renad Z. Sagdeev, Hans-Martin Vieth
Summary: CIDNP is a method used to study spin-dependent radical reactions by analyzing NMR signals of their products, with coherent polarization transfer commonly occurring in low magnetic fields. This polarization transfer can efficiently polarize spins that do not acquire CIDNP directly.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Chemistry, Physical
Natalya N. Fishman, Olga B. Morozova, Hans- Martin Vieth, Alexandra V. Yurkovskaya
Summary: This study investigated the reduction of short-lived thymine radicals by tryptophan and N-acetyl tryptophan in aqueous solution across a wide pH range. The results provide insights into the chemical DNA repair process and reveal the reaction kinetics of the reduction reactions.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2022)
Article
Chemistry, Physical
Vitaly P. Kozienko, Alexey S. Kiryutin, Alexandra V. Yurkovskaya
Summary: Parahydrogen induced polarization (PHIP) is a powerful tool for enhancing weak nuclear magnetic resonance signals. This study proposes a facile route to increase the performance of PHIP transfer in experiments by optimizing the field sweep. The optimization allows for increased polarization of C-13 in complex spin systems.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Inorganic & Nuclear
V. V. Garaeva, K. A. Spiridonov, I. A. Nikovskii, A. S. Peregudov, A. S. Kiryutin, A. Yurkovskaya, A. A. Polezhaev, V. V. Novikov
Summary: A possibility to generate spin polarization of F-19 nuclei in counterions that do not form covalent bonds with the metal center is shown for the first time in newly synthesized iridium complexes through reversible binding with the substrate and parahydrogen.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Veronika V. V. Zlobina, Alexey S. S. Kiryutin, Igor A. A. Nikovskiy, Oleg I. I. Artyushin, Vitaly P. P. Kozinenko, Alexander S. S. Peregudov, Alexandra V. V. Yurkovskaya, Valentin V. V. Novikov
Summary: Parahydrogen-induced nuclear polarization significantly enhances the sensitivity of NMR spectroscopy for medical diagnostics and enables the creation of new probes for magnetic resonance imaging. In this study, unsaturated derivatives of phosphoric acid, propargyl, and allyl phosphates, are proposed as precursors for biocompatible hyperpolarized probes. The polarization transfer to H-1 and P-31 nuclei of their hydrogenation products using ALTADENA, PASADENA, and the PH-ECHO-INEPT+ pulse sequence of NMR spectroscopy resulted in a highly amplified signal, which is among the largest for parahydrogen-induced nuclear polarization transfer to the P-31 nucleus.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Biochemistry & Molecular Biology
Anton. L. L. Popov, Irina. V. V. Savintseva, Taisiya. O. O. Kozlova, Olga. S. S. Ivanova, Ivan. V. V. Zhukov, Alexander. E. E. Baranchikov, Alexandra. V. V. Yurkovskaya, Andrey. A. A. Savelov, Artem. M. M. Ermakov, Nelli. R. R. Popova, Konstantin. L. L. Ivanov, Vladimir. K. K. Ivanov
Summary: Recently, there has been a lot of interest in using human mesenchymal stem cells (hMSCs) as potential therapies for socially significant diseases. However, the biological mechanisms of hMSC action after transplantation are still not well understood. This study reports on the use of heavily gadolinium-doped cerium oxide nanoparticles as a non-toxic and effective theranostic tool for tracking hMSCs using magnetic resonance imaging (MRI).
Article
Chemistry, Physical
Olga B. Morozova, Natalya N. Fishman, Alexandra V. Yurkovskaya
Summary: This study describes the application of time-resolved chemically induced dynamic nuclear polarization (TR CIDNP) in determining the bimolecular rate constants of triplet quenching. A known quenching rate constant was used as a reference to calculate the desired rate constants. The experiment focused on the quenching reaction of the triplet excited photosensitizer TCBP by histidine-containing compounds.
Article
Chemistry, Physical
Bogdan A. Rodin, Vineeth Thalakottoor, Mathieu Baudin, Nicolas Birilirakis, Geoffrey Bodenhausen, Alexandra V. Yurkovskaya, Daniel Abergel
Summary: Dynamical nuclear polarization (DNP) is a powerful method for polarizing spin-bearing nuclei through transferring electron polarization via microwave irradiation. In this study, the effects of energy transfer and spin temperature between proton (H) and deuterium (D) nuclei in DNP experiments were investigated using protonated or deuterated TEMPOL radicals as polarizing agents. The kinetic parameters and heat capacities of different reservoirs were analyzed to predict the behavior of heteronuclei. Experimental results also provided insights into the hidden spins that are not directly observable due to their proximity to the radicals.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Olga B. Morozova, Alexandra V. Yurkovskaya
Summary: This study investigated the reduction of carnosine radicals in neutral and basic aqueous solutions by l-tryptophan, N-acetyl tryptophan, and the Trp-Gly peptide using time-resolved chemically induced dynamic nuclear polarization (TR CIDNP). The reduction reaction rate constants were found to be influenced by the protonation state of the non-reacting β-alanine residue of carnosine radicals. Clear differences were observed compared to the reduction of histidine and N-acetyl histidine radicals, as well as the reduction of radicals derived from Gly-His, a homologue of carnosine.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Olga B. Morozova, Maksim P. Geniman, Mikhail S. Panov, Natalya N. Fishman, Alexandra V. Yurkovskaya, Peter S. Sherin
Summary: This work investigates the sites of H/H+ transfer within kynurenic acid (KNA) using the time-resolved chemically induced dynamic nuclear polarization (TR CIDNP) method. Density functional theory (DFT) calculations reveal that the KNA anion radical exists in two tautomeric forms, with H/H+ transfer to the carbonyl oxygen of the keto- or oxo-quinolinate forms, and without any significant H/H+ transfer to the nitrogen of the enol form.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Review
Chemistry, Multidisciplinary
Gerd Buntkowsky, Franziska Theiss, Jonas Lins, Yuliya A. Miloslavina, Laura Wienands, Alexey Kiryutin, Alexandra Yurkovskaya
Summary: Nuclear Magnetic Resonance (NMR) spectroscopy and Magnetic Resonance Imaging (MRI) are essential analytical and diagnostic tools with a wide range of applications. However, the low sensitivity of magnetic resonance poses a major challenge in various fields. Parahydrogen induced polarization (PHIP) is a cost-effective method to enhance signal by utilizing chemical reactions. This article provides an overview of PHIP techniques and reviews current literature on method developments and applications.
