jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Marius Jakoby
Source: Repository KITopen (Karlsruhe Institute of Technology) (article, 2021-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Investigating Exciton Dynamics by Photoluminescence Quenching Experiments in Metal-Organic Frameworks and Thermally Activated Delayed Fluorescence Emitters Photoluminescence ; Fluorescence ; Metal-organic framework ; Quenching (fluorescence) ; Exciton ; Materials science ; Photochemistry ; Nanotechnology ; Chemistry ; Chemical physics ; Optoelectronics ; Physical chemistry ; Physics ; Adsorption ; Optics ; Condensed matter physics Organic and Molecular Conductors Research ; Metal-Organic Frameworks: Synthesis and Applications ; Electrochemical Analysis and Applications
Authors: Anjali Patwardhan | Ritimukta Sarangi | Bojana Ginovska | Simone Raugei | Stephen W. Ragsdale
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2021-01-26)
Field: Chemistry — Inorganic Chemistry

Nickel-Sulfonate Mode of Substrate Binding for Forward and Reverse Reactions of Methyl-SCoM Reductase Suggest a Radical Mechanism Involving Long Range Electron Transfer ABSTRACT Methyl-coenzyme M reductase (MCR) catalyzes both synthesis and anaerobic oxidation of methane (AOM). Its catalytic site contains Ni at the core of Cofactor F 430 . The Ni ion, in its low-valent Ni(I) state lights the fuse leading to homolysis of the C-S bond of methyl-coenzyme M (methyl-SCoM) to generate a methyl radical, which abstracts a hydrogen atom from Coenzyme B (HSCoB) to generate methane and the mixed disulfide CoMSSCoB. Direct reversal of this reaction activates methane to initiate anaerobic methane oxidation. Based on crystal structures, which reveal a Ni-thiol interaction between Ni(II)-MCR and inhibitor CoMSH, a Ni(I)-thioether complex with substrate methyl-SCoM has been transposed to canonical MCR mechanisms. Similarly, a Ni(I)-disulfide with CoMSSCoB is proposed for the reverse reaction. However, this Ni(I)-sulfur interaction poses a conundrum for the proposed hydrogen atom abstraction reaction because the &gt;6 Å distance between the thiol group of SCoB and the thiol of SCoM observed in the structures appears too long for such a reaction. Spectroscopic, kinetic, structural and computational studies described here establish that both methyl-SCoM and CoMSSCoB bind to the active Ni(I) state of MCR through their sulfonate groups, forming a hexacoordinate Ni(I)-N/O complex, not Ni(I)-S. These studies rule out direct Ni(I)-sulfur interactions in both substrate-bound states. As a solution to the mechanistic conundrum, we propose that both forward and reverse MCR reactions emanate through long-range electron transfer from Ni(I)-sulfonate complexes with methyl-SCoM or CoMSSCoB, respectively. Chemistry ; Thioether ; Methane sulfonate ; Stereochemistry ; Hydrogen atom abstraction ; Thiol ; Nickel ; Medicinal chemistry ; Photochemistry ; Methyl group ; Homolysis ; Electron transfer ; Substrate (aquarium) ; Kinetic isotope effect ; Radical ; Organic chemistry Metal-Catalyzed Oxygenation Mechanisms ; CO2 Reduction Techniques and Catalysts ; Metalloenzymes and iron-sulfur proteins
Authors: Ashli Brown | M. Ángeles Muñoz Fernández | Shaquan Parker | ZeAndra D. Whitfield | Xiaomei Zheng | Ghislain R Mandouma
Source: International Journal for Innovation Education and Research (article, 2021-09-01)
Field: Materials Science — Polymers and Plastics

Synthesis and Antibacterial Property of An Encapsulated Sulfonamide Nanoparticle in a Multidisciplinary Approach Multigram quantity of a novel Sulfa Drug complex -poly(amido)amine-sulfonamide or PAMAM-Sulfa- was synthesized, from commercially available materials. It was characterized with spectroscopic methods such as nuclear magnetic resonance (NMR). The Kirby-Bauer test was used to test it against gram positive and/or gram negative bacteria using different concentrations of an ethanol solution of the PAMAM-Sulfa complex. The goal of this experiment was to synthesize and study the effect of water soluble encapsulated sulfonamides on common bacteria by undergraduate students engaging in research involving more than one STEM discipline. Students synthesized a dendrimer-sulfonamide complex before evaluating its antibiotic properties. In doing so, students employed research methods that are common to chemistry, biology and nanoscience while also learning about mechanism of infectious diseases, drugs and drug resistance. This project allowed students to combine aspects of scientific research that are usually done separately, and an opportunity to observe the seamlessness of multidisciplinary science. Sulfonamide ; Multidisciplinary approach ; Combinatorial chemistry ; Chemistry ; Amine gas treating ; Organic chemistry ; Sociology ; Social science Dendrimers and Hyperbranched Polymers ; Antimicrobial agents and applications ; Chemical Synthesis and Analysis
Authors: Tom Kunde | Tobias Pausch | Bernd M. Schmidt
Source: ChemRxiv (preprint, 2021-03-11)
Field: Chemistry — Organic Chemistry

Supramolecular Alloys from Fluorinated Hybrid [4+6] Imine Cages To create innovative materials, efficient control and engineering of pore sizes and their characteristics, crystallinity and stability is required. Eight hybrid [4+6] imine cages with a tuneable degree of fluorination and one fully fluorinated [4+6] imine cage are investigated. Although the fluorinated and the non-fluorinated building blocks used herein differ vastly in reactivity, we are able to gain control over the outcome of the self-assembly process, by carefully controlling the feed ratio. This represents the first hybrid material based on fluorinated/hydrogenated porous organic cages (POCs). These alloys with unlimited miscibility in the solid state were obtained as highly crystalline samples after recrystallization and even showed retention of the crystal lattice. All alloys and the fully fluorinated [4+6] imine cage were analysed by MALDI-MS, SCXRD, PXRD and in regards to thermal stability (TGA). &lt;br&gt; Crystallinity ; Imine ; Materials science ; Recrystallization (geology) ; Miscibility ; Thermal stability ; Supramolecular chemistry ; Chemical engineering ; Crystal structure ; Polymer chemistry ; Organic chemistry ; Chemistry ; Polymer ; Catalysis ; Composite material Supramolecular Chemistry and Complexes ; Metal-Organic Frameworks: Synthesis and Applications ; Supramolecular Self-Assembly in Materials
Authors: Danyang Liu | Zhou ZhiJian | Hao Liu
Source: E3S Web of Conferences (article, 2021-01-01)
Field: Chemistry — Organic Chemistry

The Theoretical Total Synthesis of an Aromatic Esters of the Crinane Amaryllidaceae Alkaloid Ambelline ABSTRACT. A series of crinane-type alkaloid ambelline derivatives were assessed for their potency to inhibit both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), which has been shown to be effective medicine for the treatment of Alzheimer’s disease. However, no enzyme modification has been reported total synthesis. In this work, two possible theoretical synthesis paths of Crinane-type alkaloid ambelline were discussed in this article. The major difficulty of the proposed synthesis was the synthesis of the quaternary carbon. One of the approaches emphasized on the reactions between cyclic and heterocyclic compounds and substrates on the intermediates to generate the quaternary carbon shown on the desired product. The other approach utilized series of amine reactions and Michael addition to create the precursor for the reactant in the Diels-Alder reaction and, therefore, the quaternary carbon, and finally, the desired natural product was obtained after a weak acid workup. The synthesis of ambelline has the potential to provide new pathways for treatment of Alzheimer’s disease. Butyrylcholinesterase ; Quaternary carbon ; Alkaloid ; Total synthesis ; Natural product ; Chemistry ; Acetylcholinesterase ; Amine gas treating ; Amaryllidaceae Alkaloids ; Amaryllidaceae ; Organic chemistry ; Stereochemistry ; Combinatorial chemistry ; Enzyme ; Enantioselective synthesis ; Aché ; Catalysis ; Biology Chemical synthesis and alkaloids ; Cancer Treatment and Pharmacology ; Advanced Synthetic Organic Chemistry
Authors: Luciano F. Boesel | Sebastian Ulrich | Xiaopu Wang | Xiao‐Hua Qin
Source: CHIMIA International Journal for Chemistry (article, 2021-10-11)
Field: Materials Science — Materials Chemistry

When Photoswitches Meet 3D-Printing ISSN:0009-4293 Nanotechnology ; 3D printing ; Computer science ; Materials science Photochromic and Fluorescence Chemistry ; Interactive and Immersive Displays ; Visual Attention and Saliency Detection
Authors: Roman Kleinmans | Omar Apolinar | Joseph Derosa | Malkanthi K. Karunananda | Zi‐Qi Li | Van Tran | Steven R. Wisniewski | Keary M. Engle
Source: ChemRxiv (preprint, 2021-03-03)
Field: Chemistry — Organic Chemistry

Nickel-Catalyzed 1,2-Diarylation of Alkenyl Ketones: A Comparative Study of Carbonyl-Directed Reaction Systems A conjunctive cross-coupling reaction of alkenyl ketones, aryl iodides, and arylboronic esters under nickel catalysis is reported. The reaction delivers the desired 1,2-diarylated products with moderate to excellent regiocontrol using a diverse array of ketone starting materials, as illustrated across over 40 examples. To showcase the versatility of this method, a representative product is diversified into a wide range of synthetically useful building blocks, that are not readily accessible via existing 1,2-diarylation reactions. Preliminary mechanistic studies shed light on the binding mode of the substrate, and Hammett analysis shows the effect of electronic factors on initial rates. To our knowledge, this method represents the first example of catalytic 1,2-diarylation of an alkene, directed by a native ketone functional group. Ketone ; Catalysis ; Substrate (aquarium) ; Nickel ; Aryl ; Alkene ; Chemistry ; Combinatorial chemistry ; Organic chemistry Catalytic C–H Functionalization Methods ; Catalytic Cross-Coupling Reactions ; Sulfur-Based Synthesis Techniques
Authors: Jafar I. Khan | Maha A. Alamoudi | Neha Chaturvedi | Raja Shahid Ashraf | Mohammed N. Nabi | Anastasia Markina | Wenlan Liu | Top Archie Dela Peña | Weimin Zhang | Olivier Alévêque | George T. Harrison | Wejdan Alsufyani | Eric Levillain | Stefaan De Wolf | Denis Andrienko | Iain McCulloch | Frédéric Laquai
Source: Advanced Energy Materials (article, 2021-07-01)
Field: Materials Science — Polymers and Plastics

Organic Solar Cells: Impact of Acceptor Quadrupole Moment on Charge Generation and Recombination in Blends of IDT‐Based Non‐Fullerene Acceptors with PCE10 as Donor Polymer (Adv. Energy Mater. 28/2021) In article number 2100839, Jafar I. Khan, Frédéric Laquai and co-workers report on the impact of the energetic landscape of non-fullerene acceptors on charge generation and recombination in organic bulk heterojunction solar cells. The acceptor's quadrupole moment plays a key role in determining the device efficiency and thus is an important material parameter in the design of novel non-fullerene acceptor molecules. Fullerene ; Acceptor ; Materials science ; Organic solar cell ; Charge (physics) ; Quadrupole ; Recombination ; Polymer solar cell ; Polymer ; Photovoltaic system ; Chemical physics ; Moment (physics) ; Photochemistry ; Solar cell ; Atomic physics ; Optoelectronics ; Condensed matter physics ; Physics ; Chemistry ; Organic chemistry ; Composite material ; Quantum mechanics Conducting polymers and applications ; Polymer Nanocomposite Synthesis and Irradiation ; Organic Electronics and Photovoltaics
Authors: Shivan Bissesar | Davita M. E. van Raamsdonk | Dáire Gibbons | René M. Williams
Source: Preprints.org (preprint, 2021-12-07)
Field: Chemistry — Physical and Theoretical Chemistry

Spin Orbit Coupling in Orthogonal Charge Transfer States: (TD-)DFT of Pyrene - Dimethylaniline The conformational dependence of the matrix element for spin-orbit coupling and of the electronic coupling for charge separation are determined for an electron donor-acceptor system containing a pyrene acceptor and a dimethylaniline donor. Different kinetic and energetic aspects that play a role in the spin-orbit charge transfer intersystem crossing (SOCT-ISC) mechanism are discussed. This includes parameters related to initial charge separation and the charge recombination pathways using the (Semi-Classical) Marcus Theory for electron transfer. The spin-orbit coupling, which plays a significant role in charge recombination to the triplet state can be probed by (TD-)DFT, using the latter as a tool to understand and predict the SOCT-ISC mechanism. The matrix elements for spin-orbit coupling for acetone and 4-thio-thymine are used for benchmarking. (Time Dependent-) Density Functional Theory (DFT and TD-DFT) calculations are applied using the quantum chemical program Amsterdam Density Functional (ADF). Intersystem crossing ; Density functional theory ; Chemistry ; Charge (physics) ; Spin–orbit interaction ; Coupling (piping) ; Marcus theory ; Dimethylaniline ; Electron transfer ; Triplet state ; Excited state ; Molecular physics ; Chemical physics ; Computational chemistry ; Photochemistry ; Atomic physics ; Materials science ; Physics ; Condensed matter physics ; Quantum mechanics ; Kinetics ; Reaction rate constant Photochemistry and Electron Transfer Studies ; Porphyrin and Phthalocyanine Chemistry ; Molecular Junctions and Nanostructures
Authors: Shivan Bissesar | Davita M. E. van Raamsdonk | Dáire Gibbons | René M. Williams
Source: Preprints.org (preprint, 2021-12-16)
Field: Chemistry — Physical and Theoretical Chemistry

Spin Orbit Coupling in Orthogonal Charge Transfer States: (TD-)DFT of Pyrene - Dimethylaniline The conformational dependence of the matrix element for spin-orbit coupling and of the electronic coupling for charge separation are determined for an electron donor-acceptor system containing a pyrene acceptor and a dimethylaniline donor. Different kinetic and energetic aspects that play a role in the spin-orbit charge transfer intersystem crossing (SOCT-ISC) mechanism are discussed. This includes parameters related to initial charge separation and the charge recombination pathways using the (Semi-Classical) Marcus Theory for electron transfer. The spin-orbit coupling, which plays a significant role in charge recombination to the triplet state can be probed by (TD-)DFT, using the latter as a tool to understand and predict the SOCT-ISC mechanism. The matrix elements for spin-orbit coupling for acetone and 4-thio-thymine are used for benchmarking. (Time Dependent-) Density Functional Theory (DFT and TD-DFT) calculations are applied using the quantum chemical program Amsterdam Density Functional (ADF). Intersystem crossing ; Density functional theory ; Chemistry ; Charge (physics) ; Coupling (piping) ; Spin–orbit interaction ; Spin (aerodynamics) ; Marcus theory ; Electron transfer ; Molecular physics ; Excited state ; Chemical physics ; Atomic physics ; Computational chemistry ; Photochemistry ; Materials science ; Physics ; Condensed matter physics ; Quantum mechanics ; Thermodynamics ; Reaction rate constant Photochemistry and Electron Transfer Studies ; Molecular Junctions and Nanostructures ; Porphyrin and Phthalocyanine Chemistry
Authors: Mohamed Mounder Kouicem
Source: theses.fr (ABES) (preprint, 2021-10-01)
Field: Materials Science — Surfaces, Coatings and Films

Adhesion of aluminum films to PMMA : the potential of cold plasma treatments Adhesion ; Plasma ; Materials science ; Aluminium ; Composite material ; Physics Surface Modification and Superhydrophobicity ; Copper Interconnects and Reliability ; Metal and Thin Film Mechanics
Authors: Yi Yu | Yimin Jiang | Shao‐Fen Wu | Zhaojiang Shi | Jinnan Wu | Yaofeng Yuan | Ke‐Yin Ye
Source: ChemRxiv (preprint, 2021-08-16)
Field: Chemistry — Organic Chemistry

Electrochemistry Enabled Selective Vicinal Fluorosulfenylation and Fluorosulfoxidation of Alkenes Both sulfur and fluorine play important roles in organic synthesis, the life science, and materials science. The direct incorporation of these elements into organic scaffolds with precise control of the oxidation states of sulfur moieties is of great significance. Herein, we report the highly selective electrochemical vicinal fluorosulfenylation and fluorosulfoxidation reactions of alkenes, which were enabled by the unique ability of electrochemistry to dial in the potentials on demand. Preliminary mechanistic investigations revealed that the fluorosulfenylation reaction proceeded through a radical-polar crossover mechanism involving a key episulfonium ion intermediate. Subsequent electrochemical oxidation of fluorosulfides to fluorosulfoxides were readily achieved under a higher applied potential with the adventitious H2O in the reaction mixture. Vicinal ; Electrochemistry ; Chemistry ; Sulfur ; Reaction mechanism ; Combinatorial chemistry ; Organic chemistry ; Catalysis ; Electrode ; Physical chemistry Sulfur-Based Synthesis Techniques ; Radical Photochemical Reactions ; E-Government and Public Services
Authors: Bao‐Nguyen T. Nguyen | John D. Thoburn | Angela B. Grommet | Duncan J. Howe | Tanya K. Ronson | Hugh Ryan | Jeanne L. Bolliger | Jonathan R. Nitschke
Source: ChemRxiv (preprint, 2021-03-16)
Field: Chemistry — Organic Chemistry

Coordination Cages Transport Molecular Cargoes Across Liquid Membranes &lt;p&gt;&lt;b&gt;Chemical purifications are critical processes across many industries, requiring 10 - 15% of humanity’s global energy budget&lt;/b&gt;&lt;sup&gt;1,2&lt;/sup&gt;&lt;b&gt;. Coordination cages are able to catch and release guest molecules based upon their size and shape&lt;/b&gt;&lt;sup&gt;3,4&lt;/sup&gt;&lt;b&gt;, providing a new technological basis for achieving chemical separation. Here we show that aqueous solutions of Fe&lt;sup&gt;II&lt;/sup&gt;&lt;sub&gt;4&lt;/sub&gt;L&lt;sub&gt;6&lt;/sub&gt; and Co&lt;sup&gt;II&lt;/sup&gt;&lt;sub&gt;4&lt;/sub&gt;L&lt;sub&gt;4&lt;/sub&gt; cages can be used as liquid membranes. Selective transport of complex hydrocarbons across these membranes enabled the separation of target compounds from mixtures under ambient conditions. The kinetics of cage-mediated cargo transport are governed by guest binding affinity. Using sequential transport across two consecutive membranes, target compounds were isolated from a mixture in a size-selective fashion. The selectivities of both cages thus enabled a two-stage separation process to isolate a single compound from a mixture of physicochemically similar molecules.&lt;/b&gt;&lt;/p&gt; Chemistry ; Membrane ; Molecule ; Stereochemistry ; Aqueous solution ; Crystallography ; Biochemistry ; Physical chemistry ; Organic chemistry Supramolecular Chemistry and Complexes ; Porphyrin and Phthalocyanine Chemistry ; Surface Chemistry and Catalysis
Authors: Duncan V. Mifsud | Perry A. Hailey | Alejandra Traspas Muiña | Olivier Auriacombe | N. J. Mason | S. Ioppolo
Source: Frontiers in Astronomy and Space Sciences (preprint, 2021-11-29)
Field: Chemistry — Spectroscopy

The Role of Terahertz and Far-IR Spectroscopy in Understanding the Formation and Evolution of Interstellar Prebiotic Molecules Stellar systems are often formed through the collapse of dense molecular clouds which, in turn, return copious amounts of atomic and molecular material to the interstellar medium. An in-depth understanding of chemical evolution during this cyclic interaction between the stars and the interstellar medium is at the heart of astrochemistry. Systematic chemical composition changes as interstellar clouds evolve from the diffuse stage to dense, quiescent molecular clouds to star-forming regions and proto-planetary disks further enrich the molecular diversity leading to the evolution of ever more complex molecules. In particular, the icy mantles formed on interstellar dust grains and their irradiation are thought to be the origin of many of the observed molecules, including those that are deemed to be “prebiotic”; that is those molecules necessary for the origin of life. This review will discuss both observational (e.g., ALMA, SOFIA, Herschel) and laboratory investigations using terahertz and far-IR (THz/F-IR) spectroscopy, as well as centimeter and millimeter spectroscopies, and the role that they play in contributing to our understanding of the formation of prebiotic molecules. Mid-IR spectroscopy has typically been the primary tool used in laboratory studies, particularly those concerned with interstellar ice analogues. However, THz/F-IR spectroscopy offers an additional and complementary approach in that it provides the ability to investigate intermolecular interactions compared to the intramolecular modes available in the mid-IR. THz/F-IR spectroscopy is still somewhat under-utilized, but with the additional capability it brings, its popularity is likely to significantly increase in the near future. This review will discuss the strengths and limitations of such methods, and will also provide some suggestions on future research areas that should be pursued in the coming decade exploiting both space-borne and laboratory facilities. Interstellar medium ; Astrobiology ; Interstellar ice ; Astrochemistry ; Spectroscopy ; Physics ; Molecule ; Infrared spectroscopy ; Terahertz radiation ; Molecular cloud ; Chemical physics ; Interstellar cloud ; Dark nebula ; Photoevaporation ; Abiogenesis ; Stars ; Astrophysics ; Star formation ; Astronomy ; Galaxy ; Optics Molecular Spectroscopy and Structure ; Advanced Chemical Physics Studies ; Terahertz technology and applications
Authors: M. Port | G. Hallot | Sophie Laurent | C. Gómez
Source: ORBi UMONS (article, 2021-12-02)
Field: Materials Science — Materials Chemistry

Medical Applications of Metallic Bismuth Nanoparticles peer reviewed Bismuth ; Nanoparticle ; Metal ; Metal coating Advanced Thermoelectric Materials and Devices ; Laser-Ablation Synthesis of Nanoparticles ; Chemical Reactions and Isotopes
Authors: Ali Soulieman
Source: ORI-OAI warehouse (University of Rennes) (preprint, 2021-02-24)
Field: Chemistry — Organic Chemistry

Preparation of new fluorinated analogs of GABA and development of new inhibitors of antiapoptotic proteins with anticancer activity Ces travaux entrent dans Chemistry ; Propargyl ; Apoptosis ; Molecular model ; Stereochemistry ; Combinatorial chemistry ; Biochemistry Synthesis and Biological Evaluation ; Bioactive Compounds and Antitumor Agents ; Synthesis of Organic Compounds