jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Anthony J. Campanella | Amanda Gin | Siyoung Sung | Cassidy Jackson | Roxanna Martinez | Andrew Ozarowski | Indrani Bhowmick | Joseph M. Zadrozny
Source: ChemRxiv (preprint, 2023-11-14)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Amplifying the Temperature Sensitivity of Zero-Field Splitting in Mn(II) Through Ligand Tuning Controlling the temperature response of magnetic resonance properties is an essential step toward novel molecular thermome-ters or quantum sensing platforms. To date, however, demonstrations of using molecular design to control the temperature dependence of zero-field splitting (D), a critical property that governs the electron paramagnetic resonance (EPR) response of open-shell molecules, have been absent in the literature. Herein we demonstrate that ligand design can control the temperature dependence of D. To do so, we prepared and analyzed three different encapsulated Mn2+ complexes. High-field, high-frequency EPR spectroscopy reveal EPR spectra for all complexes that vary in width as a function of temperature, indicating a change in D value. At lower temperatures, these temperature sensitivities change substantially with ligand shell and are stark, ranging from 2.2 to 9.8 MHz/K. These results are the first demonstration of the ability to tune the variable-T nature of D via ligand selection in any complex, the first for the Mn2+ metal ion, and demonstrate higher sensitivities than the NV center of diamond (74 kHz/K). Electron paramagnetic resonance ; Ligand (biochemistry) ; Chemistry ; Ion ; Resonance (particle physics) ; Spectroscopy ; Spectral line ; Paramagnetism ; Zero field splitting ; Field (mathematics) ; Analytical Chemistry (journal) ; Materials science ; Nuclear magnetic resonance ; Condensed matter physics ; Atomic physics ; Electron ; Physics Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Electron Spin Resonance Studies
Authors: Anup Gurung | Rushmika Gurung | Priyanka Kumari | Thinley Bhutia | Promodh Poudyal | Gyaltsen Pradhan
Source: ChemRxiv (preprint, 2023-08-30)
Field: Chemistry — Spectroscopy

Fabrication of Porphyrin Based Colorimetric Sensor for the Detection of Liver Cirrhosis Biomarker The early detection of liver cirrhosis biomarkers is crucial for timely medical intervention and improved patient outcomes. In this study, we present the fabrication of a novel colorimetric sensor based on porphyrin derivatives for the specific and sensitive detection of a prominent liver cirrhosis biomarker. The sensor design capitalizes on the unique optical properties of porphyrins, allowing for a rapid and visually detectable response upon biomarker binding. The synthesis and characterization of the porphyrin receptor are detailed, highlighting its structural and spectroscopic properties. The sensor's performance was evaluated using RGB analysis demonstrating exceptional selectivity and sensitivity towards the target biomarker. Importantly, the sensor's response mechanism is elucidated, shedding light on the underlying molecular interactions. The proposed porphyrin-based colorimetric sensor offers a promising avenue for the early diagnosis of liver cirrhosis, paving the way for point-of-care applications and enhancing disease management. Biomarker ; Porphyrin ; Cirrhosis ; Nanotechnology ; Computer science ; Materials science ; Medicine ; Chemistry ; Internal medicine ; Photochemistry ; Biochemistry Molecular Sensors and Ion Detection ; Advanced biosensing and bioanalysis techniques ; Lipid Membrane Structure and Behavior
Authors: Narendra Kumar Vaishanv | Nadim Eghbarieh | Rahul A. Jagtap | Ahmad Masarwa
Source: ChemRxiv (preprint, 2023-09-04)
Field: Chemistry — Organic Chemistry

Stereoselective C−B and C−H Bonds Functionalization of polyBorylated Alkenes Alkenes are fundamental functional groups which feature in various materials and bioactive molecules; however, efficient divergent strategies for their stereodefined synthesis are difficult. In this regard, numerous synthetic methodologies have been developed to construct carbon–carbon bonds with regio- and stereoselectivity, enabling the predictable and efficient synthesis of stereodefined alkenes. In fact, an appealing alternative approach for accessing challenging stereodefined alkenes molecular frameworks could involve the sequential selective activation and cross-coupling of strong bonds instead of conventional C–C bond formation. In this study, we introduce a programmed site- and stereoselective strategies that capitalizes on the versatile reactivity of readily accessible polymetalloid alkenes, through a tandem cross-coupling reaction, which is catalyzed by an organometallic Rh-complex to produce complex molecular scaffolds. By merging selective C–B and remote C–H bond functionalization, we achieve the generation of polyfunctional C(sp2)-nucleophilic species intermediates. These species can be further modified by selective coupling reactions with various C-based electrophiles, enabling the formation of C(sp2)–C(sp3) bond for the generation of even more complex molecular architectures using the readily available starting polyborylated-alkenes. Stereoselectivity ; Chemistry ; Electrophile ; Nucleophile ; Combinatorial chemistry ; Tandem ; Surface modification ; Reactivity (psychology) ; Molecule ; Coupling reaction ; Stereochemistry ; Computational chemistry ; Catalysis ; Organic chemistry ; Materials science Catalytic C–H Functionalization Methods ; Organoboron and organosilicon chemistry ; Catalytic Cross-Coupling Reactions
Authors: Ali Abdelrahman | Abdelrahman Zkria | Tsuyoshi Yoshitake
Source: Proceedings of International Exchange and Innovation Conference on Engineering & Sciences (IEICES) (article, 2023-10-19)
Field: Materials Science — Materials Chemistry

Advances in Nitrogen-Vacancy color centers in diamond for magnetometry: Advantages and Challenges Color centers in diamonds have promising and unique properties that can be optimized and engineered for several quantum-sensing applications. The negatively charged Nitrogen-vacancy (NV) center is one of the outstanding candidates due to its stable luminescence and spin features. It has a long coherence time that can be initialized and manipulated with high accuracy at room temperature. Nonetheless, many parameters, namely; nonradiative centers, complex defects, and nitrogen-based defect centers can severely affect the desirable properties of these NV centers. In this review, we highlight the recent advances of color center fabrication, parameters optimization, and current challenges to enhance these properties, with main focus on magnetometry applications. Magnetometer ; Diamond ; Vacancy defect ; Materials science ; Nitrogen ; Nuclear magnetic resonance ; Metallurgy ; Physics ; Magnetic field Diamond and Carbon-based Materials Research ; Characterization and Applications of Magnetic Nanoparticles ; Advanced Surface Polishing Techniques
Authors: Niharika Yadav | Dhirendra Singh Yadav | Preeti Varshney | Rajesh Chandra Gupta
Source: American Journal of Physics and Applications (article, 2023-11-09)
Field: Materials Science — Materials Chemistry

Electronic and Mechanical Properties of Chemical Bonds (A-O &amp; B-O) in Cubic Phase A&amp;lt;sup&amp;gt;+2&amp;lt;/sup&amp;gt;B&amp;lt;sup&amp;gt;+4&amp;lt;/sup&amp;gt;O&amp;lt;sub&amp;gt;3 &amp;lt;/sub&amp;gt;Perovskite Oxides In the present manuscript, electronic and mechanical properties of a series of ABO<sub>3</sub> (A→ alkaline earth metals, B→ transition metal) perovskites are presented. Using the plasma oscillation theory of solids, empirical relations are proposed for computation of the homopolar/ covalent gap (E<sub>h</sub>) and heteropolar/ ionic gap (E<sub>c</sub>) of the chemical bonds A-O and B-O in the cubic phase of ABO<sub>3 </sub>perovskites. To examine the validity of our calculated results, the average energy gap (E<sub>g</sub>), Phillips ionicity (f<sub>i</sub>) and covalence (f<sub>c</sub>) of the chemical bonds of these perovskites are investigated. The dielectric constant (ε<sub>∞</sub>) and refractive index (n) are computed and the results obtained are analyzed in comparison to results obtained by different researchers and these are found in fairly good agreement. Electronic polarizability (α<sub>total</sub>) was calculated through a well-known phenomenological Clausius-Mossotti relation and the values were found in accord with the results obtained from the Chemla’s relation. Further, a simple Neumann scaling approach has been employed to estimate the bulk modulus of these materials using the Phillips ionicity model. Present estimations are found in excellent agreement with the available experimental reports as compared to other such previous theoretical reports. This report supports the composition of new perovskites and hereto perceives their other properties for optoelectronics, photonics, mechanical and thermoelectric devices. Chemistry ; Nucleotide ; Phase (matter) ; Biochemistry ; Organic chemistry Thermal Expansion and Ionic Conductivity ; Transition Metal Oxide Nanomaterials ; Microwave Dielectric Ceramics Synthesis
Authors: Isheta Majumdar | Francesco Goto | Alberto Calloni | Guglielmo Albani | Lamberto Duò | Marco Finazzi | F. Ciccacci | Gianlorenzo Bussetti
Source: Applied Surface Science (article, 2023-06-17)
Field: Materials Science — Materials Chemistry

Porphyrin central metal ion driven self-assembling in heterogeneous ZnTPP – CoTPP films grown on Fe(0 0 1)-p(1 × 1)O Metal tetraphenylporphyrins (MTPPs, with M = Zn, Co) deposited on an oxygen-passivated Fe substrate, namely Fe(001)-p(1 × 1)O, were studied to understand the mechanism of molecular self-assembling on ultrathin metal-oxide films. These were characterized by photoemission spectroscopy (PES) and low energy electron diffraction (LEED). Heterogenous MTPP monolayers (ZnTPP + CoTPP) were grown at room temperature by depositing a sub-monolayer of ZnTPP on Fe(001)-p(1 × 1)O followed by a sub-monolayer of CoTPP or vice-versa, or by co-deposition. Homogeneous layers are characterized by markedly different molecular superstructures, as shown by LEED. Conversely, heterogeneous monolayers reflected an even more complex behavior: in particular, it was observed that the deposition of a small amount of CoTPP before or simultaneous to the dosing of ZnTPP molecules was able to stabilize a (5 × 5)R37° diffraction pattern, characteristic of homogeneous CoTPP, whereas homogeneous ZnTPP layers are associated to a straight (5 × 5) one. The observed differences in the ordering of the molecular self-assembling as a consequence of combining the two MTPPs highlights a significant influence of one MTPP over the other depending upon the central metal ion and not upon the molecular skeleton. Monolayer ; Porphyrin ; Oxide ; Electron diffraction ; X-ray photoelectron spectroscopy ; Metal ; Diffraction ; Substrate (aquarium) ; Chemistry ; Low-energy electron diffraction ; Homogeneous ; Crystallography ; Molecule ; Deposition (geology) ; Photoemission spectroscopy ; Materials science ; Nanotechnology ; Photochemistry ; Chemical engineering ; Optics ; Organic chemistry Porphyrin and Phthalocyanine Chemistry ; Molecular Junctions and Nanostructures ; Analytical Chemistry and Sensors
Authors: Emmanuel Picheau | Ferdinand Hof | Sara Amar | Alain Derré | Alain Pénicaud
Source: Angewandte Chemie (article, 2023-04-06)
Field: Materials Science — Materials Chemistry

Burning Graphite Faster than Carbon Black: A Case of Diffusion Control Abstract External diffusion may be exploited as a tool to purify materials in a way thought to be inaccessible from a chemical reactivity point of view. A mixture of two carbonaceous materials, graphite and carbon black, are thermally oxidized in either i) outside total diffusion‐limited regime or ii) total diffusion‐limited regime. Depending on the treatment applied it is possible to purify either graphite, a trivial task, or carbon black, a task thought impossible. Introducing geometrical selectivity, controlled total diffusion‐limited chemistry exceeds by far the field of carbon materials and can be used as an engineering tool for many materials purification, original synthesis, or to introduce asymmetry in a system. Several examples for direct applications of the findings are mentioned. Graphite ; Carbon black ; Diffusion ; Carbon fibers ; Reactivity (psychology) ; Nanotechnology ; Chemistry ; Materials science ; Chemical engineering ; Chemical physics ; Organic chemistry ; Thermodynamics ; Physics ; Composite material ; Engineering Carbon Nanotubes in Composites ; Zeolite Catalysis and Synthesis ; Graphene research and applications
Authors: Alexandra A. Heidecker | Michele Stasi | A. W. Spears | Job Boekhoven | Alexander Pöthig
Source: ChemPlusChem (article, 2023-06-12)
Field: Chemistry — Organic Chemistry

Silver and Gold Pillarplex Pseudorotaxanes from α,ω‐Dicarboxylic Acids A series of pseudorotaxanes with supramolecular organometallic silver(I) and gold(I) pillarplexes acting as rings and different α,ω-dicarboxylic acids as axle components are reported. The successful formation of the host-guest complexes is shown by <sup>1</sup> H NMR spectroscopy and respective NMR titration. Additional evaluation with ITC titration experiments yielded dissociation constants (K<sub>d</sub> ) ranging from 10<sup>-5</sup> to 10<sup>-7</sup> M. Single-crystal X-Ray diffraction analysis reveals a particularly exciting pore alignment of different examples in the solid state depending on the length of the guest. The work highlights, that dicarboxylic acids can penetrate the tight tubular pillarplex pore, paving the way to future mechanically interlocked molecules and materials. Chemistry ; Dicarboxylic acid ; Nanotechnology ; Combinatorial chemistry ; Organic chemistry ; Materials science Supramolecular Chemistry and Complexes ; Metal complexes synthesis and properties ; Magnetism in coordination complexes
Authors: Steven Herzberg | Suveen N. Mathaudhu | Lorenzo Mangolini
Source: Plasma Processes and Polymers (article, 2023-05-12)
Field: Materials Science — Ceramics and Composites

Nonthermal plasma synthesis of silicon carbonitride Abstract The use of a low‐temperature plasma for the synthesis of amorphous silicon carbonitride (SiCN) nanoparticles enables the realization of sintered bulk samples with high thermal stability. Amorphous SiCN nanoparticles are produced from a mixture of silane, methane, and ammonia utilizing a mid‐pressure, radio‐frequency, continuous flow reactor. Particle characterization shows that the nanoparticles are largely amorphous with some crystalline silicon and silicon carbide domains &lt;10 nm in size. Compositional tuning, controlled by varying the precursor flow rates, coupled with the uniform mixing of elements at the nanoscale, results in samples that resist crystallization even when sintered at temperatures as high as 2000°C. This study suggests that the low‐temperature plasma synthesis of nanoparticles has great potential to produce bulk structural materials for application in harsh environments. Materials science ; Chemical engineering ; Silane ; Nanoparticle ; Silicon ; Amorphous solid ; Amorphous silicon ; Crystallization ; Silicon carbide ; Particle (ecology) ; Nanotechnology ; Plasma ; Nanocrystalline silicon ; Crystalline silicon ; Composite material ; Metallurgy ; Crystallography ; Chemistry Advanced ceramic materials synthesis ; Diamond and Carbon-based Materials Research ; Semiconductor materials and devices
Authors: Matthias Smuda | Noah Elsner | Jonas Ströh | Nicole Pienack | Rastko Radulovic | Azat Khadiev | Huayna Terraschke | Michael Ruck | Thomas Doert
Source: ChemistryOpen (article, 2023-12-13)
Field: Chemistry — Organic Chemistry

<i>In situ</i> Investigations of the Formation Mechanism of Metastable <i>γ</i>‐BiPd Nanoparticles in Polyol Reductions Synthesizing intermetallic phases containing noble metals often poses a challenge as the melting points of noble metals often exceed the boiling point of bismuth (1560 °C). Reactions in the solid state generally circumvent this issue but are extremely time consuming. A convenient method to overcome these obstacles is the co-reduction of metal salts in polyols, which can be performed within hours at moderate temperatures and even allows access to metastable phases. However, little attention has been paid to the formation mechanisms of intermetallic particles in polyol reductions. Identifying crucial reaction parameters and finding patterns are key factors to enable targeted syntheses and product design. Here, we chose metastable γ-BiPd as an example to investigate the formation mechanism from mixtures of metal salts in ethylene glycol and to determine critical factors for phase formation. The reaction was also monitored by in situ X-ray diffraction using synchrotron radiation. Products, intermediates and solutions were characterized by (in situ) X-ray diffraction, electron microscopy, and UV-Vis spectroscopy. In the first step of the reaction, elemental palladium precipitates. Increasing temperature induces the reduction of bismuth cations and the subsequent rapid incorporation of bismuth into the palladium cores, yielding the γ-BiPd phase. Intermetallic ; Bismuth ; Ethylene glycol ; Nanoparticle ; Melting point ; Polyol ; Palladium ; Metastability ; Noble metal ; Chemistry ; Phase (matter) ; Powder diffraction ; Materials science ; Metal ; Chemical engineering ; Nanotechnology ; Crystallography ; Catalysis ; Organic chemistry Nanomaterials for catalytic reactions ; Catalytic Processes in Materials Science ; Mesoporous Materials and Catalysis
Authors: Eva Deitmann | Kai Dahms | Michael Maskos | Dirk Ziegenbalg | Gabriele Menges‐Flanagan
Source: ChemRxiv (preprint, 2023-09-05)
Field: Chemistry — Organic Chemistry

Selectivity of Grignard reagent formation – from semi-batch to continuous lab and pilot scale The formation of Grignard reagents from metallic magnesium and a halide is often accompanied by the formation of the Wurtz coupling product, an undesired side product formed by the reaction of a Grignard reagent molecule and a halide molecule. By using a scale-up approach from semi-batch type synthesis to continuous lab and pilot scale for various Grignard reagents, it is demonstrated that a continuous production process can improve Grignard reagent selectivity and reduce Wurtz coupling. Reagent ; Halide ; Selectivity ; Grignard reagent ; Magnesium ; Chemistry ; Grignard reaction ; Combinatorial chemistry ; Coupling reaction ; Organic chemistry ; Catalysis Coordination Chemistry and Organometallics ; Inorganic Chemistry and Materials ; Catalytic Cross-Coupling Reactions
Authors: Kamoladdin Saidov | Roy Shrawan | Jamoliddin Razzokov | Shavkat Mamatkulov | Odilkhuja Parpiev | Olim Ruzimuradov
Source: E3S Web of Conferences (article, 2023-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

The fabrication and characterization of ZnO/NiCO2O4 nanowires synthesized by a hydrothermal method The main functional part of the supercapacitors and nanogenerators made up of various types of nanostructured materials. The contemporary devices have been manufactured employing different kinds of nanomaterials based on nanoflake and nanowire structures. These hierarchical materials show high efficiency on engineering electrodes for supercapacitors as well as piezoelectric for nanogenerators. Here, we have successfully synthesized NiCo2O4 nanowires on ZnO nanoflakes by applying two-step hydrothermal method which is absent similar analogous to date. The microscopic analysis has shown the uniform growth of NiCo2O4 nanowires on ZnO nanoflakes. This fabricated material might be used in above mentioned purposes in the future. Materials science ; Nanowire ; Hydrothermal circulation ; Supercapacitor ; Nanomaterials ; Nanotechnology ; Fabrication ; Characterization (materials science) ; Piezoelectricity ; Nanogenerator ; Electrode ; Chemical engineering ; Electrochemistry ; Composite material ; Chemistry Supercapacitor Materials and Fabrication ; ZnO doping and properties ; Advanced Sensor and Energy Harvesting Materials
Authors: Franco Dinelli | Michele Modestino | Armando Galluzzi | Tamara Posati | Mirko Seri | R. Zamboni | Giovanna Sotgiu | M. Polichetti
Source: Nanomaterials (article, 2023-07-08)
Field: Materials Science — Materials Chemistry

Magnetic Analysis of MgFe Hydrotalcites as Powder and Dispersed in Thin Films within a Keratin Matrix Hydrotalcites (HTlcs) are a class of nanostructured layered materials that may be employed in a variety of applications, from green to bio technologies. In this paper, we report an investigation on HTlcs made of Mg and Fe, recently employed to improve the growth in vitro of osteoblasts within a keratin sponge. We carried out an analysis of powder materials and of HTlcs dispersed in keratin and spin-coated on a Si/SiO<sub>2</sub> substrate at different temperatures. A magnetic study of the powders was carried out with a Quantum Design Physical Property Measurement System equipped with a Vibrating Sample Magnetometer. The data gathered prove that these HTlcs are fully paramagnetic, and keratin showed a very small magnetic response. Optical and Atomic Force Microscopy analyses of the thin films provide a detailed picture of clusters randomly dispersed in the films with various dimensions. The magnetic properties of these films were characterized using the Nano Magneto Optical Kerr Effect (NanoMOKE) down to 7.5 K. The data collected show that the local magnetic properties can be mapped with a micrometric resolution distinguishing HTlc regions from keratin ones. This approach opens new perspectives in the characterization of these composite materials. Materials science ; Characterization (materials science) ; Paramagnetism ; Hydrotalcite ; Keratin ; Matrix (chemical analysis) ; Substrate (aquarium) ; Magnetization ; Thin film ; Magnetometer ; Nanocomposite ; Composite material ; Chemical engineering ; Nanotechnology ; Magnetic field ; Organic chemistry ; Chemistry ; Condensed matter physics Layered Double Hydroxides Synthesis and Applications ; Intestinal and Peritoneal Adhesions ; Iron oxide chemistry and applications