jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Alexey V. Bogdanov | Alexey Bobrovsky | Andrey Kh. Vorobiev
Source: Physical Chemistry Chemical Physics (article, 2021-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Optimization of the photo-orientation rate of an azobenzene-containing polymer based on a kinetic model of photoinduced ordering The explicit dependence of the rate of photoinduced ordering (photo-orientation) of an azobenzene-containing liquid-crystalline polymer on the photostationary concentration of cis-azobenzene has been predicted theoretically and found experimentally. The employed kinetic model based on the photoinduced rearrangement of the domain structure of a liquid-crystalline material predicts the maximum rate of photo-orientation at ca. 50% content of the cis-isomer in the photostationary state of irradiation. For experimental fine tuning of the photostationary trans-cis ratio, the simultaneous irradiation of material with two beams of light with different wavelengths was employed. The excellent agreement of theory and experiment indicates that the difference of photostationary fractions of cis-azobenzene fragments in adjacent domains of different orientations is the driving force of photoinduced ordering. Azobenzene ; Orientation (vector space) ; Polymer ; Azo compound ; Kinetic energy ; Photostationary state ; Materials science ; Photochemistry ; Kinetics ; Chemistry ; Polymer chemistry ; Photoisomerization ; Organic chemistry ; Physics ; Isomerization ; Catalysis ; Composite material ; Geometry ; Mathematics ; Classical mechanics Liquid Crystal Research Advancements ; Photochromic and Fluorescence Chemistry ; Advanced Materials and Mechanics
Authors: Dimitrinka Arabadzhieva | Anna Y. Gyurova | Ivan L. Minkov | Alexander Chinarev | Elena Mileva
Source: Colloids and Surfaces A Physicochemical and Engineering Aspects (article, 2021-09-21)
Field: Materials Science — Biomaterials

Fine-tuning of bulk and interfacial characteristics of two-antennary oligoglycines in aqueous solutions Aqueous solution ; Supramolecular chemistry ; Amphiphile ; Chemical physics ; Nanocarriers ; Chemistry ; Dynamic light scattering ; Nanotechnology ; Materials science ; Chemical engineering ; Molecule ; Polymer ; Organic chemistry ; Drug delivery ; Nanoparticle Supramolecular Self-Assembly in Materials ; Molecular Sensors and Ion Detection ; Surfactants and Colloidal Systems
Authors: Roberto Sánchez‐Naya | Vladimir Stepanenko | Karl Mandel | Florian Beuerle
Source: Organic Materials (article, 2021-01-01)
Field: Materials Science — Materials Chemistry

Modulation of Crystallinity and Optical Properties in Composite Materials Combining Iron Oxide Nanoparticles and Dye-Containing Covalent Organic Frameworks Two series of organic–inorganic composite materials were synthesized through solvothermal imine condensation between diketopyrrolopyrrole dialdehyde DPP-1 and 5,10,15,20-tetrakis(4-aminophenyl)porphyrin (TAPP) in the presence of varying amounts of either amino- or carboxy-functionalized superparamagnetic iron oxide nanoparticles (FeO). Whereas high FeO loading induced cross-linking of the inorganic nanoparticles by amorphous imine polymers, a lower FeO content resulted in the formation of crystalline covalent organic framework domains. All hybrid materials were analyzed by magnetization measurements, powder X-ray diffraction, electron microscopy, IR, and UV/Vis absorption spectroscopy. Crystallinity, chromophore stacking, and visible absorption features are directly correlated to the mass fraction of the components, thus allowing for a fine-tuning of materials properties. Crystallinity ; Materials science ; Nanoparticle ; Amorphous solid ; Chemical engineering ; Imine ; Hybrid material ; Superparamagnetism ; Covalent bond ; Polymer ; Porphyrin ; Stacking ; Absorption (acoustics) ; Chromophore ; Nanocomposite ; Polymer chemistry ; Organic chemistry ; Magnetization ; Nanotechnology ; Chemistry ; Composite material Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Porphyrin and Phthalocyanine Chemistry
Authors: Светлана Иванова | Eva Köster | Julian J. Holstein | Niklas Keller | Guido H. Clever | Thomas Bein | Florian Beuerle
Source: ChemRxiv (preprint, 2021-03-03)
Field: Materials Science — Materials Chemistry

Isoreticular Crystallization of Highly Porous Cubic Covalent Organic Cage Compounds &lt;p&gt;Modular frameworks featuring well-defined pore structures in microscale domains establish tailor-made porous materials. For open molecular solids however, maintaining long-range order after desolvation is inherently challenging, since packing is usually governed by only a few supramolecular interactions. Here we report on two series of nanocubes obtained by co-condensation of two different hexahydroxy tribenzotriquinacenes (TBTQs) and benzene-1,4-diboronic acids (BDBAs) with varying linear alkyl chains in 2,5-position. &lt;sup&gt;n&lt;/sup&gt;Butyl groups at the apical position of the TBTQ vertices yielded soluble model compounds, which were analyzed by mass spectrometry and NMR spectroscopy. In contrast, methyl-substituted cages spontaneously crystallized as isostructural and highly porous solids with BET surface areas and pore volumes of up to 3426 m&lt;sup&gt;2&lt;/sup&gt; g&lt;sup&gt;−1&lt;/sup&gt; and 1.82 cm&lt;sup&gt;3&lt;/sup&gt; g&lt;sup&gt;−1&lt;/sup&gt;. Single crystal X-ray diffraction and sorption measurements revealed an intricate cubic arrangement of alternating micro- and mesopores in the range of 0.97–2.2 nm that are fine-tuned by the alkyl substituents at the BDBA linker.&lt;/p&gt; Isostructural ; Crystallography ; Chemistry ; Mesoporous material ; Crystallization ; Alkyl ; Supramolecular chemistry ; Iodide ; Sorption ; Crystal structure ; Physical chemistry ; Organic chemistry ; Adsorption Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Supramolecular Chemistry and Complexes
Authors: Zi‐Qi Li | Omar Apolinar | Ruohan Deng | Keary M. Engle
Source: ChemRxiv (preprint, 2021-05-25)
Field: Chemistry — Organic Chemistry

Directed Markovnikov Hydroarylation and Hydroalkenylation of Alkenes Under Nickel Catalysis We report a full account of our research on nickel-catalyzed Markovnikov-selective hydroarylation and hydroalkenylation of non-conjugated alkenes, which has yielded a toolkit of methods that proceed under mild conditions with alkenyl sulfonamide, ketone, and amide substrates. Regioselectivity is controlled through catalyst coordination to the native Lewis basic functional groups contained within these substrates. To maximize product yield, reaction conditions were fine-tuned for each substrate class, reflecting the different coordination properties of the directing functionality. Detailed kinetic and computational studies shed light on the mechanism of this family of transformations, pointing to transmetalation as the turnover-limiting step. Markovnikov's rule ; Transmetalation ; Regioselectivity ; Chemistry ; Catalysis ; Yield (engineering) ; Nickel ; Combinatorial chemistry ; Amide ; Lewis acids and bases ; Ketone ; Substrate (aquarium) ; Organic chemistry ; Materials science Catalytic C–H Functionalization Methods ; Asymmetric Hydrogenation and Catalysis ; Cyclopropane Reaction Mechanisms
Authors: Christian D. Buch | Steen Honoré Hansen | Dmitri Mitcov | Camilla Mia Tram | Gary S. Nichol | Euan K. Brechin | Stergios Piligkos
Source: ChemRxiv (preprint, 2021-02-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Design of Pure Heterodinuclear Lanthanoid Cryptate Complexes Heterolanthanide complexes are difficult to synthesize owing to the similar chemistry of the lanthanide ions. Conse-quently, very few purely heterolanthanide complexes have been synthesized. This is despite the fact that such complexes hold inter-esting optical and magnetic properties. To fine-tune these properties, it is important that one can choose complexes with any given combination of lanthanides. Herein we report a synthetic procedure which yields pure heterodinuclear lanthanide cryptates LnLn*LX3 (X = NO3- or OTf-) based on the cryptand H3L = N[(CH2)2N=CH-R-CH=N-(CH2)2]3N (R = m-C6H2OH-2-Me-5). In the synthesis the choice of counter ion and solvent prove crucial in controlling the Ln-Ln*composition. Choosing the optimal solvent and counter ion affords pure heterodinuclear complexes with any given combination of Gd(III)-Lu(III) including Y(III). To demon-strate the versatility of the synthesis all dinuclear combinations of Y(III), Gd(III), Yb(III) and Lu(III) were synthesized resulting in 10 novel complexes of the form LnLn*L(OTf)3 with LnLn* = YbGd 1, YbY 2, YbLu 3, YbYb 4, LuGd 5, LuY 6, LuLu 7, YGd 8, YY 9 and GdGd 10. Through the use of 1H, 13C NMR and mass spectrometry the heterodinuclear nature of YbGd, YbY, YbLu, LuGd, LuY and YGd was confirmed. Crystal structures of LnLn*L(NO3)3 reveal short Ln-Ln distances of ~3.5 Å. Using SQUID magnetometry the exchange coupling between the lanthanide ions was found to be anti-ferromagnetic for GdGd and YbYb while ferromagnetic for YbGd. Lanthanide ; Cryptand ; Chemistry ; Crystallography ; Solvent ; Ion ; Crystal structure ; Stereochemistry ; Organic chemistry Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Organometallic Complex Synthesis and Catalysis
Authors: Christian D. Buch | Steen Honoré Hansen | Dmitri Mitcov | Camilla Mia Tram | Gary S. Nichol | Euan K. Brechin | Stergios Piligkos
Source: ChemRxiv (preprint, 2021-02-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Design of Pure Heterodinuclear Lanthanoid Cryptate Complexes Heterolanthanide complexes are difficult to synthesize owing to the similar chemistry of the lanthanide ions. Conse-quently, very few purely heterolanthanide complexes have been synthesized. This is despite the fact that such complexes hold inter-esting optical and magnetic properties. To fine-tune these properties, it is important that one can choose complexes with any given combination of lanthanides. Herein we report a synthetic procedure which yields pure heterodinuclear lanthanide cryptates LnLn*LX3 (X = NO3- or OTf-) based on the cryptand H3L = N[(CH2)2N=CH-R-CH=N-(CH2)2]3N (R = m-C6H2OH-2-Me-5). In the synthesis the choice of counter ion and solvent prove crucial in controlling the Ln-Ln*composition. Choosing the optimal solvent and counter ion affords pure heterodinuclear complexes with any given combination of Gd(III)-Lu(III) including Y(III). To demon-strate the versatility of the synthesis all dinuclear combinations of Y(III), Gd(III), Yb(III) and Lu(III) were synthesized resulting in 10 novel complexes of the form LnLn*L(OTf)3 with LnLn* = YbGd 1, YbY 2, YbLu 3, YbYb 4, LuGd 5, LuY 6, LuLu 7, YGd 8, YY 9 and GdGd 10. Through the use of 1H, 13C NMR and mass spectrometry the heterodinuclear nature of YbGd, YbY, YbLu, LuGd, LuY and YGd was confirmed. Crystal structures of LnLn*L(NO3)3 reveal short Ln-Ln distances of ~3.5 Å. Using SQUID magnetometry the exchange coupling between the lanthanide ions was found to be anti-ferromagnetic for GdGd and YbYb while ferromagnetic for YbGd. Lanthanide ; Cryptand ; Chemistry ; Solvent ; Crystallography ; Ion ; Crystal structure ; Stereochemistry ; Organic chemistry Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Metal complexes synthesis and properties
Authors: Vidmantas Bieliūnas | Sigitas Stončius
Source: ChemCatChem (article, 2021-06-29)
Field: Chemistry — Organic Chemistry

Fine‐Tuning the Bicyclo[3.3.1]nona‐2,6‐diene Ligands: Second Generation 4,8‐Substituted Dienes for Rh‐Catalyzed Asymmetric 1,4‐Addition Reactions Abstract Design and synthesis of the second generation C 2 ‐symmetric 4,8‐ endo,endo ‐bis(alkoxy) bicyclo[3.3.1]nona‐2,6‐diene ligands possessing additional 4,8‐ exo,exo substituents is reported. The 4,8‐ exo,exo groups provide a further element for fine‐tuning of the ligand structure by enforcing conformational rigidity of the 4,8‐ endo,endo side chains. Such tetrasubstituted bicyclo[3.3.1]nona‐2,6‐dienes were employed as steering ligands in the rhodium‐catalyzed arylation of cyclic enones with arylboronic acids, providing the corresponding 1,4‐addition products in good to excellent yields (69–99 %) and enantioselectivities up to 99 % ee. Chemistry ; Diene ; Bicyclic molecule ; Rhodium ; Ligand (biochemistry) ; Catalysis ; Alkoxy group ; Stereochemistry ; Medicinal chemistry ; Organic chemistry ; Receptor Cyclopropane Reaction Mechanisms ; Synthetic Organic Chemistry Methods ; Asymmetric Synthesis and Catalysis
Authors: Rohan Dekate | V Suryanarayanan | Prashant Sharma | Ashok Reddi
Source: SAE International Journal of Advances and Current Practices in Mobility (article, 2021-09-22)
Field: Materials Science — Materials Chemistry

Model Based Design, Simulation and Experimental Validation of SCR Efficiency Model &lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;Selective Catalytic Reduction is a key technology, used for NOx abatement. There are several models available for SCR system performance out of which most are experimentally verified only in flow reactors with simulated gaseous concentration and standard test conditions. But in the vehicle as well as in the engine test bench the conditions are very much dynamic compared to the simulated conditions of the lab. This transient behaviour emphasizes the need for a best fit model which accommodates the real-world dynamic conditions, thus reducing the overall effort in SCR catalyst selection for any given engine or vehicle application. The primary objective of this paper is to derive an empirical and mathematical efficiency model for SCR catalyst performance through a model-based design approach. The output from the model is compared with the experimental results from the vehicle and engine test bench, to validate the model accuracy. The model is a function of system specific parameters like space velocity, NO2 ratio, system efficiency, catalyst loading and ageing factors, temperature mapping, for various engine operating zones that are benchmarked from existing experimental results and chemical kinetics that are already incorporated in existing models. This model is fine-tuned by incorporating experimental data and simulated with different control strategies to further refine and optimize the catalyst performance and reduce DEF consumption and ammonia slip formation. The model output from numerical simulations and experimental results are used to derive the control strategy for the best overall efficiency model.&lt;/div&gt;&lt;/div&gt; Test bench ; NOx ; Computational fluid dynamics ; Simulation ; Reduction (mathematics) ; Selective catalytic reduction ; Automotive engineering ; Engineering ; Computer science ; Mechanical engineering ; Catalysis ; Chemistry Catalytic Processes in Materials Science ; Industrial Gas Emission Control ; Catalysis and Oxidation Reactions
Authors: Sambit Das | Salini Senthil | Sabyasachi Chakraborty | Raghunathan Ramakrishnan
Source: ChemRxiv (preprint, 2021-05-03)
Field: Chemistry — Organic Chemistry

All Hands on Deck: Accelerating Ab Initio Thermochemistry via Wavefunction Approximations We accelerate the G4(MP2) composite model by fine-tuning the individual steps using resolution-of-identity and domain‐based local pair‐natural orbitals. The new variant, G4(MP2)-XP, has a low prediction error when tested on 1694 benchmark molecules. To showcase the method's relevance for large molecules, we determine and present a new reference value for the standard formation enthalpy of buckminsterfullerene. We expect G4(MP2)-XP to become the de facto method for rapid and accurate production of thermochemistry big data. Thermochemistry ; Wave function ; Ab initio ; Atomic orbital ; Standard enthalpy of formation ; Computational chemistry ; Benchmark (surveying) ; Computer science ; Chemistry ; Physics ; Theoretical physics ; Atomic physics ; Thermodynamics ; Quantum mechanics Chemical Thermodynamics and Molecular Structure ; Advanced Chemical Physics Studies ; Computational Drug Discovery Methods
Authors: E.G. Deze | Maria D. Bareka | Dionysios S. Karousos | Andreas A. Sapalidis | Evangelos P. Favvas
Source: Materials Today Proceedings (article, 2021-03-14)
Field: Materials Science — Materials Chemistry

Mesoporous silica based copper catalytic materials for potential deNOx application: Synthesis and characterization Mesoporous material ; Catalysis ; Materials science ; Copper ; Porosity ; Chemical engineering ; Characterization (materials science) ; Dispersion (optics) ; Particle size ; Stoichiometry ; Particle (ecology) ; Polyol ; Nanotechnology ; Composite material ; Organic chemistry ; Metallurgy ; Chemistry ; Polyurethane Catalytic Processes in Materials Science ; Catalysis and Oxidation Reactions ; Mesoporous Materials and Catalysis
Authors: P Rajamalli | Federica Rizzi | Wenbo Li | Michael A. Jinks | Abhishek Gupta | Beth A. Laidlaw | Ifor D. W. Samuel | Thomas J. Penfold | Stephen M. Goldup | Eli Zysman‐Colman
Source: ChemRxiv (preprint, 2021-02-03)
Field: Materials Science — Materials Chemistry

Using the Mechanical Bond to Tune the Performance of a Thermally Activated Delayed Fluorescence Emitter We report the characterization of rotaxanes based on a carbazole–benzophenone thermally activated delayed fluorescence luminophore. We find that the mechanical bond leads to an improvement in key photophysical properties of the emitter, notably an increase in photoluminescence quantum yield and a decrease in the energy difference between singlet and triplet states, as well as fine tuning of the emission wavelength, a feat that is difficult to achieve when using covalently bound substituents. Computational simulations, supported by X-ray crystallography, suggest that this tuning of properties occurs due to weak interactions between the axle and the macrocycle that are enforced by the mechanical bond. This work highlights the benefits of using the mechanical bond to refine existing luminophores, providing a new avenue for emitter optimization that can ultimately increase the performance of these molecules. Carbazole ; Benzophenone ; Common emitter ; Covalent bond ; Fluorescence ; Quantum yield ; Materials science ; Photoluminescence ; Photochemistry ; Luminophore ; Bond energy ; Singlet state ; Molecule ; Optoelectronics ; Chemistry ; Luminescence ; Excited state ; Optics ; Atomic physics ; Physics ; Organic chemistry Luminescence and Fluorescent Materials ; Supramolecular Chemistry and Complexes ; Molecular Junctions and Nanostructures
Authors: Paulina Bolek | Justyna Zeler | Carlos D. S. Brites | Joanna Trojan–Piegza | Luís D. Carlos | Eugeniusz Zych
Source: Zenodo (CERN European Organization for Nuclear Research) (article, 2021-04-20)
Field: Materials Science — Materials Chemistry

Ga-Modified YAG:Pr3+ Dual-Mode Tunable Luminescence Thermometers The temperature determination using luminescent materials is nowadays considered the perspective remote technique for temperature gauging, despite the few examples reported so far combining wide operating temperature range with satisfying relative thermal sensitivity and temperature uncertainty values. In this paper, we study the Y<sub>3</sub>(Al,Ga)<sub>5</sub>O<sub>12</sub>:0.1%Pr phosphors with controlled Ga:Al composition to deliberately affect their luminescent properties. We demonstrate that the energy barrier for thermal quenching of the 5d-4f luminescence can be effectively tailored, yielding the fine tune of the thermometric parameters of these phosphors. By exploiting time-resolved and time-integrated approaches we show that the thermometers can cover the 17–700 K temperature range with a maximum relative sensitivity up to 3.6 %·K<sup>-1</sup> and a temperature uncertainty as lower as 0.02 K. For each sample, the temperature readout of the distinct thermometric parameters is compared illustrating that the performance of the thermometers should also consider the relative temperature error between the calculated and the measured temperatures, besides relative thermal sensitivity and temperature uncertainty. Dual mode ; Luminescence ; Dual (grammatical number) ; Materials science ; Optoelectronics ; Thermometer ; Physics ; Engineering ; Art ; Electronic engineering Luminescence Properties of Advanced Materials ; Spectroscopy and Laser Applications ; Advanced Semiconductor Detectors and Materials
Authors: Nargis Sultana | Muhammad Ilyas Tariq | Urooj Siddique | Maria Farooq | Muhammad Usman Khan | Saba Jamil | Muhammad Ramzan Saeed Ashraf Janjua
Source: Journal of Cluster Science (article, 2021-03-28)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Theoretical Investigation of Jack-in-the-Box Electro-Optical Compounds: In-Silico Design of Mixed-Argon Benzonitriles Towards the Template of Clusters Hyperpolarizability ; Chemistry ; Natural bond orbital ; Argon ; Polarizability ; Benzonitrile ; HOMO/LUMO ; Computational chemistry ; Molecular orbital ; Acceptor ; Photochemistry ; Physical chemistry ; Density functional theory ; Organic chemistry ; Molecule Nonlinear Optical Materials Research ; Crystal Structures and Properties ; Inorganic Fluorides and Related Compounds
Authors: Charlotta G. Lebedenko | Ipsita A. Banerjee
Source: Macromolecular Theory and Simulations (article, 2021-11-18)
Field: Materials Science — Biomaterials

Investigation of Self‐Assembly of Symmetric and Asymmetric Peptide Bolaamphiphiles by COSMO‐RS and Atomistic Simulations and Their Interactions with POPC Bilayers Abstract In this work, eight new peptide bolaamphiphiles (PbAs) are designed containing polar (serine or threonine) and nonpolar amino acid head groups (tryptophan or tyrosine) connected by varying aliphatic carbon chains of different lengths and saturation. The physicochemical properties of the bolaamphiphiles are examined by COSMO‐RS to determine sigma profiles, potential, and sigma surfaces. Self‐assembly is studied using atomistic molecular dynamic simulations under protonated and deprotonated conditions. To mimic physiological conditions, simulations are also carried out in the presence of sodium chloride and the impact of salt on the self‐assembly process is also studied. In general, hydrophobic PbAs are found to form higher‐order supramolecular structures while PbAs connected by shorter chains or hydrophilic head groups form globular, more compact structures. Self‐assembly is more favorable when the PbAs are protonated. Membrane interactions are then studied using MD simulations and the results indicate that the hydrophobic PbAs interact more favorably with the POPC membrane surfaces. These simulations provide insights about the intricate interactions and properties of the PbAs and shed light on the ability to form fine‐tuned structures at the nanoscale. This study may lead to the development of novel PbAs for potential applications in a wide variety of biological applications. POPC ; Chemistry ; Molecular dynamics ; Protonation ; Membrane ; Hydrophobic effect ; Supramolecular chemistry ; Bilayer ; Chemical physics ; Computational chemistry ; Organic chemistry ; Molecule ; Biochemistry Supramolecular Self-Assembly in Materials ; Chemical Synthesis and Analysis ; Protein Structure and Dynamics