jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Slavko Radenković | Željko Tomović
Source: ChemPhysChem (article, 2022-04-11)
Field: Chemistry — Organic Chemistry

Tuning the Structure and Properties of N‐doped Positively Charged Polycyclic Aromatic Hydrocarbons A detailed study of the geometry, aromatic character, electronic and magnetic properties for a series of positively charged N-doped polycyclic aromatic hydrocarbons (PAHs) was performed. Magnetic properties of the examined molecules were analyzed by means of the magnetically induced current density calculated using the diamagnetic-zero version of the continuous transformation of origin of current density (CTOCD-DZ) method. The comparative study of the local aromaticity of the studied molecules was performed using several different indices: energy effect (ef), harmonic oscillator model of aromaticity (HOMA) index, six centre delocalization index (SCI) and nucleus independent chemical shifts (NICS). The presence of N-atoms in the inner rings was found to cause a planarity distortion in the studied N-doped systems. The geometric changes and charged nature of the studied N-doped systems do not significantly influence the current density and the local aromaticity distribution in comparison with the corresponding parent benzenoid hydrocarbons. The present study demonstrates how quantum chemical calculations can be used for rational design of novel PAHs and for fine tuning of their properties. Aromaticity ; Delocalized electron ; Diamagnetism ; Planarity testing ; Chemistry ; Molecule ; Computational chemistry ; Doping ; Chemical shift ; Density functional theory ; Chemical physics ; Molecular physics ; Physical chemistry ; Materials science ; Organic chemistry ; Crystallography ; Physics ; Magnetic field Synthesis and Properties of Aromatic Compounds ; Fullerene Chemistry and Applications ; Graph theory and applications
Authors: Johannes Hertel | Caroline Schwinge | Lukas Gerlich | Maik Wagner‐Reetz
Source: Applied Physics Letters (article, 2022-05-30)
Field: Materials Science — Materials Chemistry

300 mm CMOS-compatible fabrication of Ru2Si3 sub-50 nm thin films and characterization We report the thermoelectric characterization of Ru2Si3 thin films. Ruthenium (VI)-silicide was formed via silicidation by rapid thermal processing of ruthenium on amorphous, undoped silicon of different thicknesses (sub-50 nm). 300 mm wafer level processes were applied, utilizing physical and chemical vapor deposition methods. High-temperature-XRD, energy dispersive x-ray spectroscopy, transmission electron microscopy, and time-of-flight secondary ion mass spectrometry confirm the formation of single-phase Ru2Si3 thin films. Thermoelectric measurements reveal exceptionally high Seebeck coefficients of up to 1.5 mV/K close to room temperature in dependence of adjustable oxide nanoskins. Due to the thermal stability of the nanoskins, fine-tuning of the thermoelectric properties by rapid thermal processing could be applied in a large temperature range. Materials science ; Thermoelectric effect ; Thin film ; Wafer ; Analytical Chemistry (journal) ; Thermal stability ; Chemical vapor deposition ; Amorphous solid ; Atmospheric temperature range ; Silicide ; Optoelectronics ; Silicon ; Characterization (materials science) ; Fabrication ; Nanotechnology ; Chemical engineering ; Chemistry ; Crystallography Advanced Thermoelectric Materials and Devices ; Semiconductor materials and interfaces ; Chalcogenide Semiconductor Thin Films
Authors: Luca Ceresa | Daniel Ta | Lauren M. Edwards | Joseph Kimball | Zygmunt Gryczyński | Sergei V. Dzyuba
Source: Journal of Photochemistry and Photobiology A Chemistry (article, 2022-12-14)
Field: Materials Science — Materials Chemistry

8-Aminoquinoline-containing squaric acid congeners as polarity and viscosity probes Squaric acid ; Moiety ; Fluorescence ; Chemistry ; Multiplexing ; Polarity (international relations) ; Nanotechnology ; Photochemistry ; Combinatorial chemistry ; Materials science ; Computer science ; Organic chemistry ; Telecommunications ; Optics ; Physics Photochromic and Fluorescence Chemistry ; Molecular Sensors and Ion Detection ; Luminescence and Fluorescent Materials
Authors: Jaume García‐Amorós | M. Cidália R. Castro | M. Manuela M. Raposo | Dolores Velasco
Source: Dyes and Pigments (article, 2022-11-29)
Field: Materials Science — Materials Chemistry

Photochromic heteroarylethenes with fast thermal isomerization kinetics Stilbenes (diphenylethenes) are fully examined organic chromophores for very diverse applications. However, these molecules might show poor stability under irradiation because several simultaneous reactions (oxidative photocyclization and dimerization) can take place during the photochemical isomerization of their CC bond. In this context, heteroarylethenes emerge as powerful counterparts thanks to their improved stability. In addition, the chosen heterocycles and their functionalization allows to fine tune and increase the speed at which the thermal back reaction occurs, broadening the scope of application of the resulting chromophores. Here we report on the thermal Z-to-E isomerization kinetics of a series of rationally designed heteroarylethenes and how the chemical architecture of the chromophore modulates the speed of the process. Specifically, the metastable Z isomers display relaxation times covering a wide time window, from a few hours to hundreds of microseconds. In fact, one of the studied dyes is the fastest photochromic switch based on heteroarylethenes. It should be also noticed that the described heteroarylethenes exhibit great photochemical stability, it being possible to switch them back and forth many times without degradation. Isomerization ; Photochromism ; Chromophore ; Photochemistry ; Chemistry ; Context (archaeology) ; Kinetics ; Microsecond ; Metastability ; Thermal stability ; Molecular switch ; Relaxation (psychology) ; Molecule ; Organic chemistry ; Catalysis Photochromic and Fluorescence Chemistry ; Luminescence and Fluorescent Materials ; Porphyrin and Phthalocyanine Chemistry
Authors: Xu Chang | Yuanyuan Ji | Manman Jia | Huichao Li
Source: Computational Materials Science (article, 2022-08-16)
Field: Materials Science — Materials Chemistry

Molecular dynamics simulations for mechanical properties of the monolayer PtS2 with line defect Zigzag ; Isotropy ; Materials science ; Anisotropy ; Monolayer ; Molecular dynamics ; Line (geometry) ; Toughness ; Composite material ; Condensed matter physics ; Optics ; Nanotechnology ; Geometry ; Physics ; Computational chemistry ; Chemistry 2D Materials and Applications ; Boron and Carbon Nanomaterials Research ; MXene and MAX Phase Materials
Authors: Reda M. Abdelhameed | Hassan Abdel‐Gawad
Source: Egyptian Journal of Chemistry (article, 2022-01-13)
Field: Chemistry — Inorganic Chemistry

Metal-Organic Frameworks (MOFs) based 2-Amino-1,4-Benzenedicarboxylic Acid linker: Synthesis and Post-Synthetic Modification Nanoporous metal-organic frameworks (MOFs) are three-dimensional porous lattices of inorganic-organic linkers. These materials have tunable physiochemical properties such as high porosity, crystalline nature, chemical, thermal and mechanical stability as well. 2-Amino-1,4-benzenedicarboxylic acid plays an important role in metal-organic frameworks synthesis and post-synthetic modification. It reacts with different metals such as: 3d-transition metal (Zn, Co, Cu, Mn, and Fe), 4d-transition metal (Cd, Ag, and Y), s-alkaline metal (Ca), p- metal (Sn and Al) and 4f-lanthanids (Er, La, Dy, Tb, Nd, Yb, Eu, Pr, Gd and Sm) to produce MOFs with different structures. The second-biggest application of 2-amino-1,4-benzenedicarboxylic in MOFs is post-synthetic modification because of the presence of the amino group, such as: IRMOF-3, DMOF-1-NH2, UMCM-1-NH2, MOF-LIC-1, MIL-53-NH2, UIO-66-NH2, MIL-101-NH2. This functionalized MOFs react with different organic reagents to produce new MOFs with new applications fields such as gas separation, catalysis, gas storage, water treatment, and other different applications. Linker ; Metal-organic framework ; Combinatorial chemistry ; Surface modification ; Metal ; Materials science ; Chemistry ; Nanotechnology ; Organic chemistry ; Computer science Metal-Organic Frameworks: Synthesis and Applications ; X-ray Diffraction in Crystallography ; Thermal and Kinetic Analysis
Authors: Ji Wang | QINGYIN WANG | GONGYING WANG
Source: TURKISH JOURNAL OF CHEMISTRY (article, 2022-01-01)
Field: Chemistry — Inorganic Chemistry

MIL-53(Al) catalytic synthesis of poly(ethylene terephthalate) Poly(ethylene terephthalate) (PET) is one of the world's five major engineering plastics and is widely used in various fields. At present, the main catalysts used in the synthesis of PET are antimony, titanium, and aluminum metal compounds. Among them, antimony-based catalysts are poisonous and the titanium-based catalyst products are relatively yellow in hue. The aluminum-based catalyst has the advantages of low price and environmental friendliness, but current research shows that the organoaluminum catalyst has the problem of hydrolysis, and MIL-53 (Al) has good stability and will not affect the environment, so we add a catalyst before the esterification reaction, and uses thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscope (SEM), and N<sub>2</sub> low-temperature physical adsorption characterizes the thermal stability and structure of MIL-53(Al). At the same time, the effects of different content, polycondensation time, before and after activation and polycondensation temperature on the properties of PET were investigated. The research results show that when the molar content of catalyst is 0.05% and the reaction temperature is 280 °C for 150 min, the product obtained is relatively excellent. The catalytic activity has almost no effect before and after activation, indicating that the polycondensation reaction is carried out on the surface of the catalyst. Therefore, MIL-53 (Al) has great potential in PET industrial catalysis. Catalysis ; Thermogravimetric analysis ; Condensation polymer ; Thermal stability ; Ethylene ; Chemistry ; Scanning electron microscope ; Adsorption ; Titanium ; Chemical engineering ; Antimony ; Polymer chemistry ; Materials science ; Organic chemistry ; Composite material Metal-Organic Frameworks: Synthesis and Applications ; Membrane Separation and Gas Transport ; Recycling and Waste Management Techniques
Authors: Felipe Robles-González | María Teresa Rodríguez Hernández | Antonio Ledezma‐Pérez | Ramón Díaz de León | Marco A. De Jesús‐Téllez | Ricardo López-González
Source: Polymers (article, 2022-10-12)
Field: Materials Science — Biomaterials

Development of Biodegradable Polyesters: Study of Variations in Their Morphological and Thermal Properties through Changes in Composition of Alkyl-Substituted (ε-DL) and Non-Substituted (ε-CL, EB, L-LA) Monomers Three series of polyesters based on monomer combinations of <i>ε</i>-caprolactone (<i>ε</i>-CL), ethylene brassylate (EB), and l-Lactide (LLA) with the alkyl substituted lactone <i>ε</i>-decalactone (<i>ε</i>-DL) were synthesized at different molar ratios. Copolymers were obtained via ring opening polymerization (ROP) employing TBD (1,5,7-triazabicyclo-[4.4.0]-dec-5-ene), an organic catalyst which can be handled under normal conditions, avoiding the use of glove box equipment. The molar monomer composition of resulting copolymers differed from theoretical values due to lower <i>ε</i>-DL reactivity; their <i>M<sub>n</sub></i> and <i>M<sub>w</sub></i> values were up to 14 kDa and 22.8 kDa, respectively, and distributions were (<i>Ɖ</i>) ≤ 2.57. The thermal stability of these materials suffered due to variations in their <i>ε</i>-DL molar content. Thermal transitions such as melting (<i>T<sub>m</sub></i>) and crystallization (<i>T<sub>c</sub></i>) showed a decreasing tendency as <i>ε</i>-DL molar content increased, while glass transition (<i>T<sub>g</sub></i>) exhibited minor changes. It is worth mentioning that changes in monomer composition in these polyesters have a strong impact on their thermal performance, as well as in their crystallization degree. Consequently, variations in their chemical structure may have an effect on hydrolyic degradation rates. It should be noted that, in future research, some of these copolymers will be exposed to hydrolytic degradation experiments, including characterizations of their mechanical properties, to determine their adequacy in potential use in the development of soft medical devices. Polyester ; Monomer ; Thermal stability ; Alkyl ; Copolymer ; Glass transition ; Polymer chemistry ; Materials science ; Crystallization ; Polymerization ; Reactivity (psychology) ; Ring-opening polymerization ; Organic chemistry ; Polymer ; Chemistry ; Composite material biodegradable polymer synthesis and properties ; Electrospun Nanofibers in Biomedical Applications ; Bone Tissue Engineering Materials
Authors: Rasha A. Baseer | Ewies F. Ewies | A. M. Ismail
Source: Journal of Polymer Research (article, 2022-06-30)
Field: Materials Science — Polymers and Plastics

Synthesis, optical and dielectric properties of polyacryloyloxy imino fluorophenyl acetamide and polyacryloyloxy imino fluorophenyl acetamide-co-polystyrene sulfonate Abstract Our scope is synthesis a new poly fluorobenzamide oxime ester and study its structural, optical, and dielectric properties. Consequently, (( E )-2-((acryloyloxy)imino)- N -(4-fluorophenyl) acetamide) ( AIFPA ) was as-synthesized via a condensation reaction of ( E )- N -(4-fluorophenyl)-2-(hydroxyimino) acetamide with acrylic acid to polymerize it via free radical polymerization ( PAIFPA ). over and above, the synthesized PAIFPA was inserted in more polymerization action with polystyrene sulfonate through the grafting process (PAIFPA-co-PSS). The chemical structures and morphology of AIFPA, PAIFPA, and PAIFPA-co-PSS were characterized by 1H NMR, FTIR, and XRD. The crystallinity index of PAIFPA, and PAIFPA-co-PSS was studied, affording that PAIFPA-co-PSS has the highest crystallinity. Moreover, The optical bandgap that obtained from absorbance analysis was encountered to be in the range of 2.6 eV to 3.5 eV. Ultimately, the dielectric properties of PAIFPA, and PAIFPA-co-PSS showed that electric conductivity values ranged from 6.12 × 10 –8 to 7.11 × 10 –7 S.cm −1 , and 5.48 × 10 –10 to 7.75 × 10 –8 S.cm −1 , respectively. It has a great deal of interest of PAIFPA-co-PSS which has wide band gap energy as short-wavelength light absorbers to be used in tandem polymer solar cells. Materials science ; Acetamide ; Crystallinity ; Polymerization ; Polymer chemistry ; Band gap ; Dielectric ; Polystyrene sulfonate ; Fourier transform infrared spectroscopy ; Polystyrene ; Polymer ; Nuclear chemistry ; Chemical engineering ; Organic chemistry ; Composite material ; Chemistry ; PEDOT:PSS Conducting polymers and applications ; Polymer Nanocomposite Synthesis and Irradiation ; Synthesis and properties of polymers
Authors: Charlotte Koschnick | Stefano Canossa | Maxwell W. Terban | Ruggero Frison | Martin Etter | Felix A. Böhm | Davide Μ. Proserpio | Simon Krause | Robert E. Dinnebier | Bettina V. Lotsch
Source: ChemRxiv (preprint, 2022-12-22)
Field: Chemistry — Inorganic Chemistry

Unlocking new Topologies in Zr-based Metal–Organic Frameworks by Combining Linker Flexibility and Building Block Disorder The outstanding diversity of Zr-based frameworks is inherently linked to the variable coordination geometry of Zr-oxo clusters and the conformational flexibility of the linker, both of which allow for different framework topologies based on the same linker–cluster combination. In addition, intrinsic structural disorder provides a largely unexplored handle to further expand the accessibility of novel metal–organic frameworks (MOFs) structures that can be formed. In this work we report the concomitant synthesis of three topologically different MOFs based on the same M6O4(OH)4 clusters (M = Zr or Hf) and methane-tetrakis(p-biphenyl-carboxylate) (MTBC) linkers. Two novel structural models are presented based on single crystal diffraction analysis, namely cubic c (4,12)MTBC-M6 and trigonal tr (4,12)MTBC-M6, which comprise 12-coordinated clusters and 4 coordinated tetrahedral linkers. Notably, the cubic phase features a new architecture based on orientational cluster disorder, which is essential for its formation and has been analyzed by a combination of average structure refinements and diffuse scattering analysis from both powder and single crystal X-ray diffraction data. The trigonal phase also features structure disorder, although involving both linkers and secondary building units. In both phases, remarkable geometrical distortion of the MTBC linkers illustrates how linker flexibility is also essential for their formation and expands the range of achievable topologies in Zr-based MOFs and its analogues. Linker ; Metal-organic framework ; Crystallography ; Materials science ; Cluster (spacecraft) ; Tetrahedron ; Topology (electrical circuits) ; Network topology ; Crystal structure ; Diffraction ; Chemistry ; Computer science ; Mathematics ; Physics ; Combinatorics Metal-Organic Frameworks: Synthesis and Applications ; Magnetism in coordination complexes ; X-ray Diffraction in Crystallography
Authors: Xin Jin | Hui Jiang | Yi Chen | Xin Han | Ken Sun | Linlin Shi | Xin‐Qi Hao | Mao‐Ping Song
Source: Nanomaterials (article, 2022-12-09)
Field: Materials Science — Materials Chemistry

A Cavity-Tailored Metal-Organic Tetrahedral Nanocage and Gas Adsorption Property Porous organometallic nanomaterials are a new class of materials based on a three-dimensional structure. They have excellent applications in different fields, but their applications in gas storage and separation have not been fully developed. CO<sub>2</sub> adsorption storage and hydrocarbon separation has been a challenging industrial problem. Several typical molecular adsorbents have been used to study the separation, but the problems of long-term stability, high selectivity and synthetic complexity of these adsorbents remain to be solved. Here, we have designed and synthesized tetrahedral metal supramolecular nanocage with custom cavities based on the unique rigid structure of triptycene derivatives. Using the unique discrete porous structure of tetrahedral metal nanocages, the gas adsorption and separation performance of the metal supramolecular nanocage was investigated. By analyzing the adsorption and desorption isotherms and the multi-component competitive adsorption curves, we noticed that the tetrahedral supramolecular nanocages had good CO<sub>2</sub> storage capacity and good separation capacity for C<sub>2</sub>H<sub>2</sub>/CO<sub>2</sub> and C<sub>2</sub>H<sub>2</sub>/N<sub>2</sub>. All these indicate that porous organic metal nanomaterials are expected to be a new energy saving separation material. Nanocages ; Adsorption ; Materials science ; Nanomaterials ; Supramolecular chemistry ; Chemical engineering ; Gas separation ; Porosity ; Metal-organic framework ; Desorption ; Nanotechnology ; Organic chemistry ; Molecule ; Chemistry ; Composite material ; Catalysis Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Supramolecular Chemistry and Complexes
Authors: Wei Wei | Zeng‐Xia Zhao | Bao‐Hui Xia | Wei Li
Source: Frontiers in Chemistry (article, 2022-09-01)
Field: Materials Science — Materials Chemistry

Theoretical analysis of expanded porphyrins: Aromaticity, stability, and optoelectronic properties Expanded porphyrin systems are capable of binding a variety of substrates due to their increased cavity size and aromatic nature, holding important applications as magnetic resonance imaging contrast agents and as sensitizers for photodynamic therapy. It is there of fundamental interest to know the photoelectrical properties of expanded porphyrins using quantum chemistry calculations. In this work, we theoretically designed and screened a series of expanded porphyrins by incorporating terthiophene (TTH) and dithienothiophene (DTT) moieties. Our calculations showed that all the designed molecules exhibit excellent optoelectronic performance than the reference molecule. It is suggested that the porphyrin molecule with TTH moiety has better stability than the one with DTT moiety. Finally, we demonstrated that molecule <b>2</b> features with TTH moiety and the inverted selenophene ring outperform other molecules because it exhibits increased HOMO-LUMO gap, planar geometry, and strengthened aromaticity. We expect that this work can provide theoretical guidelines for the design of novel porphyrin materials. Moiety ; Porphyrin ; Aromaticity ; Molecule ; HOMO/LUMO ; Small molecule ; Photochemistry ; Chemistry ; Materials science ; Computational chemistry ; Stereochemistry ; Organic chemistry Porphyrin and Phthalocyanine Chemistry ; Synthesis and Properties of Aromatic Compounds ; Luminescence and Fluorescent Materials
Authors: Adam F. Cahn | Rebecca L. Combs | Ellen M. Monzo | Steven D. Prinslow | Celina M. Harris | R. Lee Penn
Source: Journal of Crystal Growth (article, 2022-10-13)
Field: Chemistry — Inorganic Chemistry

Onion-Like nanoparticles of the metal–organic framework UiO-66 synthesized by sequential spike crystal growth Zirconium ; Nanoparticle ; Transmission electron microscopy ; Metal-organic framework ; Scanning electron microscope ; Particle (ecology) ; Facet (psychology) ; Materials science ; Crystal (programming language) ; Particle size ; Metal ; Chemical engineering ; Nanotechnology ; Crystallography ; Chemistry ; Physical chemistry ; Composite material ; Metallurgy Metal-Organic Frameworks: Synthesis and Applications ; Polyoxometalates: Synthesis and Applications ; Catalytic Processes in Materials Science
Authors: Lina Yin | Ting Guan | Jie Cheng | Dongchao Pan | Jinyang Lu | Jiahui Huang | Jiaqi Wu | Xiaoli Chen | Taiyun You | Xuting Huo | Yuting He | Jiayun Pang | Qingzhong Hu
Source: Communications Chemistry (article, 2022-10-29)
Field: Chemistry — Organic Chemistry

Manipulations of phenylnorbornyl palladium species for multicomponent construction of a bridged polycyclic privileged scaffold Hexahydromethanocarbazole is a privileged scaffold in the discovery of new drugs and photoactive organic materials due to its good balance between structural complexity and minimized entropy penalty upon receptor binding. To address the difficulty of synthesizing this highly desirable bridged polycyclic scaffold, we designed a convenient multicomponent reaction cascade as intercepted Heck addition/C-H activation/C-palladacycle formation/electrophilic attack of ANP/N-palladacycle formation/Buchwald amination. A distinguishing feature of this sophisticated strategy is the successive generation of two key phenylnorbornyl palladium species to control the reaction flow towards desired products. DFT calculations further reveal the crucial roles of Cs<sub>2</sub>CO<sub>3</sub> and 5,6-diester substitutions on the norbornene reactant in preventing multiple side-reactions. This innovative method exhibits a broad scope with good yields, and therefore will enable the construction of natural-product-like compound libraries based on hexahydromethanocarbazole. Scaffold ; Palladium ; Chemistry ; Nanotechnology ; Materials science ; Engineering ; Organic chemistry ; Catalysis ; Biomedical engineering Catalytic Cross-Coupling Reactions ; Catalytic C–H Functionalization Methods ; Covalent Organic Framework Applications