jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Pathik Sahoo
Source: Crystal Growth & Design (article, 2024-04-08)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Introducing Dihedral Angle Torsion in a Flexible Dicarboxylic Acid: Evolution from a Sequential Symmetry Condensing Liquid Crystalline Gel to a Step-Halting Heat-Set Gel Through systematic molecular engineering, versatile properties can be incrementally introduced into supramolecular materials. Nonetheless, even a minor internal modification in the molecular backbone can outperform the conventional molecular engineering approach to fine-tune its corresponding supramolecular properties. A dicarboxylate salt, categorically primary ammonium dicarboxylate (PAD) salt derived from a flexible dicarboxylic acid such as adipic acid, imparts conformational flexibility to the salt in gelling solvents. This results in the exhibition of sequential symmetry condensing the liquid crystal gel against rising temperatures. Gentle heating can unzip van der Waals interactions, showcasing a gradual 2D to 0D phase-changing ability and generating liquid crystalline properties. Such gradual symmetry reduction quantifies the entropy enhancement during heating. On the other hand, the manipulation of dihedral angle torsion within a dicarboxylic acid backbone offers a means to tailor solubility. By increasing the dihedral angle torsion, the molecule loses alignment against the solvent’s polarity or temperature, resulting in insolubility and conformational rigidity. Conversely, manipulating dihedral angle torsion within a dicarboxylic acid backbone provides a means to tailor solubility. Increasing dihedral angle torsion causes the molecule to lose alignment against the solvent’s polarity or temperature, resulting in insolubility and conformational rigidity. Incorporating higher dihedral angle torsion energy, such as introducing an azo or ferrocene backbone into a dicarboxylic acid, renders the resulting molecule resistant to solubilization, even at high temperatures, resulting in a heat-set gel. This transformation turns sequential symmetry-condensing liquid crystal gelator molecules into two-step halting polymorphic state-based heat-set gelator molecules. This review demonstrates that a conventional functional group is not always mandatory for introducing supramolecular properties. Instead, a physical parameter, such as dihedral angle torsion, can be generated to finely tune the thermostatic properties in developing supramolecular heat-set or liquid crystal gels. Dihedral angle ; Torsion (gastropod) ; Crystallography ; Dicarboxylic acid ; Materials science ; Symmetry (geometry) ; Chemistry ; Geometry ; Mathematics ; Organic chemistry ; Polymer chemistry ; Molecule ; Hydrogen bond Liquid Crystal Research Advancements ; Advanced Materials and Mechanics ; Supramolecular Self-Assembly in Materials
Authors: Jieying Li | Chris A. J. Klaassen | Peilong Li | Arkaye Kierulf | Mohammad Yaghoobi | Leila Khazdooz | Amin Zarei | James Smoot | Yong Lak Joo | Alireza Abbaspourrad
Source: Carbohydrate Polymers (article, 2024-10-22)
Field: Materials Science — Biomaterials

Using gas-assisted electrospinning to design rod-shaped particles from starch for thickening agents and Pickering emulsifiers Thickening ; Electrospinning ; Starch ; Chemical engineering ; Pickering emulsion ; Polymer science ; Thickening agent ; Materials science ; Chemistry ; Composite material ; Nanotechnology ; Nanoparticle ; Organic chemistry ; Polymer ; Engineering Electrospun Nanofibers in Biomedical Applications ; Pickering emulsions and particle stabilization ; biodegradable polymer synthesis and properties
Authors: Yumeng Gao | H. Miao | Jie Qian | Yuan Yao | Jiayin Yuan | Shaoliang Lin
Source: Macromolecules (article, 2024-06-06)
Field: Materials Science — Materials Chemistry

Tailoring Self-Assembly of Alternating Copolymers for Ordered and Crystalline 2D Nanostructures via Diverse Strategies The pursuit of ordered two-dimensional (2D) materials with customized properties has fueled extensive research. While many established fabrication methods rely on substrates, solution-based polymer self-assembly processes remain much unexplored. Here, by manipulating the delicate balance between dominating and competing forces, we demonstrate how polymer chains fold, self-adjust, and self-assemble into diverse ordered 2D nanostructures in solution guided by an energy landscape, especially highly ordered crystalline structures, which are of great challenge to realize by polymers. An alternating copolymer initially self-assembled into 2D planar flakes via a kinetic pathway, lacking crystallinity. Through thermal annealing, they overcame a local kinetic barrier, in situ transforming into 2D circular crystalline clusters. Furthermore, by facilely replacing alkenyl linkers with triazoles in the alternating copolymers, additional tunable competing interactions were introduced, enabling the system to take thermodynamically favored pathways from the beginning and form 2D crystalline spindles directly. Besides, both the systems exhibited reversible self-assembly behavior and remote-controllable merit under light irradiation, forming 2D crystalline structures including flowers and spindles, respectively, highlighting the systems’ responsiveness and versatility. This study offers diverse and facile strategies for constructing and fine-tuning tailorable nanostructures, suggesting promising applications in precision engineering and biomedical technologies. Copolymer ; Self-assembly ; Nanostructure ; Materials science ; Nanotechnology ; Polymer chemistry ; Liquid crystalline ; Polymer science ; Polymer ; Composite material Covalent Organic Framework Applications ; Block Copolymer Self-Assembly ; Supramolecular Self-Assembly in Materials
Authors: Yuriy N. Luponosov | Alexander N. Solodukhin | Nikolay Aseyev | Tatyana I. Rokitskaya | Д. Е. Колотова | Еlena А. Kotova | T. S. Kurkin | Liya A. Poletavkina | Yulia A. Isaeva | Yuri N. Antonenko | П. М. Балабан | Sergey A. Ponomarenko
Source: ACS Biomaterials Science & Engineering (article, 2024-01-19)
Field: Materials Science — Materials Chemistry

Nanoparticles of Push–Pull Triphenylamine-Based Molecules for Light-Controlled Stimulation of Neuronal Activity Organic semiconductor materials with a unique set of properties are very attractive for interfacing biological objects and can be used for noninvasive therapy or detection of biological signals. Here, we describe the synthesis and investigation of a novel series of organic push-pull conjugated molecules with the star-shaped architecture, consisting of triphenylamine as a branching electron donor core linked through the thiophene π-spacer to electron-withdrawing alkyl-dicyanovinyl groups. The molecules could form stable aqueous dispersions of nanoparticles (NPs) without the addition of any surfactants or amphiphilic polymer matrixes with the average size distribution varying from 40 to 120 nm and absorption spectra very similar to those of human eye retina pigments such as rods and green cones. Variation of the terminal alkyl chain length of the molecules forming NPs from 1 to 12 carbon atoms was found to be an efficient tool to modulate their lipophilic and biological properties. Possibilities of using the NPs as light nanoactuators in biological systems or as artificial pigments for therapy of degenerative retinal diseases were studied both on the model planar bilayer lipid membranes and on the rat cortical neurons. In the planar bilayer system, the photodynamic activity of these NPs led to photoinactivation of ion channels formed by pentadecapeptide gramicidin A. Treatment of rat cortical neurons with the NPs caused depolarization of cell membranes upon light irradiation, which could also be due to the photodynamic activity of the NPs. The results of the work gave more insight into the mechanisms of light-controlled stimulation of neuronal activity and for the first time showed that fine-tuning of the lipophilic affinity of NPs based on organic conjugated molecules is of high importance for creating a bioelectronic interface for biomedical applications. Triphenylamine ; Materials science ; Photoswitch ; Nanoparticle ; Lipid bilayer ; Alkyl ; Nanomedicine ; Membrane ; Biophysics ; Amphiphile ; Molecule ; Photochemistry ; Polymer ; Nanotechnology ; Chemistry ; Organic chemistry ; Polymer chemistry Photochromic and Fluorescence Chemistry ; Photoreceptor and optogenetics research ; Supramolecular Self-Assembly in Materials
Authors: José C. J. M. D. S. Menezes | Vinícius R. Campos
Source: Compounds (article, 2024-10-10)
Field: Chemistry — Organic Chemistry

Unlocking the Potential of Hydroxycinnamic Acid Bioconjugates: Tailored Derivatives for Biomedical, Cosmetic, and Food Applications This review discusses the development and applications of bioconjugates derived from natural hydroxycinnamic acids (HCA), such as coumaric, sinapic, ferulic, and caffeic acids, combined with various biomaterials. These bioconjugates offer a range of benefits including antioxidant properties, UV protection, customized hydrophilic–lipophilic balance, improved safety, solubility, emolliency, biocompatibility, biodegradability, and targeted delivery for biomedical, cosmetic, and food applications. The increasing demand for natural products in the biomedical, cosmetic, and food industries has led to the exploration of these hydroxycinnamic acids and their derivatives. We discuss the synthesis and modification of hydroxycinnamic acids with biomaterials such as ω-hydroxy fatty acids, castor and lesquerella oils, glycerol, isosorbides, and synthetic polyethylene glycol to form functional phenolipids for biomedical, sunscreen, and skincare applications. Encapsulation techniques with β-cyclodextrins and modification of polymeric supports like polysaccharides and starch are discussed for enhancing bioavailability and solubility and targeted delivery. The fine-tuned development of bioconjugates from hydroxycinnamic acids using glycerol to modify the hydrophilic–lipophilic balance, substitution by water-soluble carboxylic acid groups, vegetable oil-based phenolipids, polysaccharides, and PEGylation provide enhanced dual functionalities and offer a promising avenue for creating effective products across various applications. Nanotechnology ; Chemistry ; Biochemical engineering ; Materials science ; Engineering Carbohydrate Chemistry and Synthesis ; Enzyme Catalysis and Immobilization ; Microbial Natural Products and Biosynthesis
Authors: Akash Shamrao Nandgaye | Kalpak Ghosh | Sharma S. R. K. C. Yamijala | K. Venkata Rao
Source: Angewandte Chemie International Edition (article, 2024-11-18)
Field: Materials Science — Materials Chemistry

An Expeditious Synthesis of Near‐Infrared‐Absorbing Imide‐Based Graphene Nanoribbons and Their Photothermal Properties Graphene nanoribbons (GNRs) with low band gap and strong near-infrared (NIR) absorption are potential candidates for optoelectronic and biomedical applications. In this context, imide-based GNRs are promising, but there are no rational design principles that yield these robust GNRs with strong NIR absorption. Here, we demonstrate a rational synthesis route to achieve NIR-absorbing imide-based robust GNRs by exploring the bay region of polyperylene (PP). Using the oxidative Diels-Alder reaction, we have successfully introduced mono and diimide functional groups on PP. After cyclodehydrogenation, the resultant GNRs, benzoperylene imide GNR (BPI-GNR) and coronene diimide GNR (CDI-GNR), show oscillatory edge geometry with strong NIR absorption (up to 1000 nm) and optical band gap of ~1.3 eV. Computational studies also indicate that imide substituents play an important role in fine-tuning the optoelectronic properties of GNRs. Moreover, these GNRs are solution-processable and can be made into thin films via spray coating. Owing to the strong NIR absorption and imide substitutions, BPI and CDI-GNRs show good photothermal conversion with excellent cyclic stability. Imide ; Materials science ; Diimide ; Graphene ; Graphene nanoribbons ; Photothermal therapy ; Absorption (acoustics) ; Band gap ; Optoelectronics ; Photochemistry ; Nanotechnology ; Chemistry ; Organic chemistry ; Polymer chemistry ; Molecule ; Composite material Graphene research and applications ; Thermal Radiation and Cooling Technologies ; Graphene and Nanomaterials Applications
Authors: Zhen Du | Junhao Dai | Zhibo Wang | Zushan Ye | Huanyu Lei | Qing‐Yun Guo | Xiaoyun Yan | Mu Li | Minzhao Li | Wenkai Zhao | Beijing Zhang | Yupeng Huang | Ziqiong Yang | Zongwu Huang | Panchao Yin | Lingxiang Jiang | Rui Zhang | Wen Tang
Source: Angewandte Chemie International Edition (article, 2024-12-23)
Field: Materials Science — Biomaterials

Engineering the Self‐Assembly Pathways of POSS‐Peptide Amphiphiles to Form Diverse Cross‐β Structures Cross-β structures are crucial in driving protein folding and aggregation. However, due to their strong aggregating tendency, the precise control of the self-assembly of β-sheet-forming peptides remains a challenge. We propose a molecular geometry strategy to study and control the self-assembly of cross-β structures. We conjugate the peptide with shape-persistent polyhedral oligomeric silsesquioxane (POSS), which acts as a hydrophilic head and senses the solvent environment. The POSS-peptide amphiphiles display two distinct self-assembly pathways: twisted nanoribbons transforming into either nanotubes at low water content or flat nanoribbons at high water content. The peptide packing in flat nanoribbons is predominantly modulated by POSS, diverting the system away from crystal formation, which is the absolute lowest energy state of pure peptide self-assemblies. For the first time, we have demonstrated that POSS can serve as a useful tool to adjust the interactions between cross-β strands, achieving fine-tuning of the pathway complexity (i.e., the kinetic and thermodynamic aspects of peptide self-assembly). With this versatile molecular platform incorporating multiple functionalities of POSS and programable peptide sequences, this study provides a platform to exploit cross-β-based nanomaterials with functional and pathological significance. Self-assembly ; Silsesquioxane ; Peptide ; Amphiphile ; Materials science ; Folding (DSP implementation) ; Molecular dynamics ; Nanotechnology ; Conjugate ; Nanomaterials ; Chemistry ; Copolymer ; Polymer ; Computational chemistry Supramolecular Self-Assembly in Materials ; Silicone and Siloxane Chemistry ; Luminescence and Fluorescent Materials
Authors: Almudena Inchausti | Rosa Mollfulleda | Marcel Swart | Josefina Perles | Santiago Herrero | Valentı́n G. Baonza | Mercedes Taravillo | Álvaro Lobato
Source: Advanced Science (article, 2024-04-03)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Torsion Effects Beyond the δ Bond and the Role of π Metal‐Ligand Interactions Previous studies on bimetallic paddlewheel compounds have established a direct correlation between metal-metal distance and ligand torsion angles, leading to the rule that higher torsion results in longer metal-metal bond distances. Here, the new discovery based on diarylformamidinate Ru₂⁵⁺ paddlewheel compounds [Ru<sub>2</sub>Cl(DArF)<sub>4</sub>] that show an opposite behavior is reported: higher torsions lead to shorter metal-metal distances. This discovery challenges the assumption that internal rotation solely impacts the δ bond. By combining experimental and theoretical techniques, it is demostrated that this trend is associated with previously overlooked π metal-ligand interactions. These π metal-ligand interactions are a direct consequence of the paddlewheel structure and the conjugated nature of the bidentate ligands. This findings offer far-reaching insights into the influence of equatorial ligands and their π-conjugation characteristics on the electronic properties of paddlewheel complexes. That this effect is not exclusive of diruthenium compounds but also occurs in other bimetallic cores such as ditungsten or dirhodium is demonstrated, and with other ligands showing allyl type conjugation. These results provide a novel approach for fine-tuning the properties of these compounds with significant implications for materials design. Bimetallic strip ; Metal ; Denticity ; Ligand (biochemistry) ; Dihedral angle ; Torsion (gastropod) ; Chemistry ; Conjugated system ; Computational chemistry ; Crystallography ; Bond length ; Chemical physics ; Stereochemistry ; Molecule ; Organic chemistry ; Crystal structure ; Hydrogen bond ; Polymer Magnetism in coordination complexes ; Organometallic Complex Synthesis and Catalysis ; Metal complexes synthesis and properties
Authors: Chengyang Zhang | Shihao Sha | Yizhao Qing | Runnan Yu | Zhan’ao Tan
Source: ACS Applied Materials & Interfaces (article, 2024-03-15)
Field: Materials Science — Materials Chemistry

One-Step Extrusion Preparation for Low-Cost Multicolored Carbon Dot Fluorescent Films Carbon dots (CDs), an emerging class of environmentally friendly luminescent materials, have been extensively applied in full-color display of light-emitting diodes (LEDs). However, the synthesis of CDs usually requires high pressure, and the conventional preparation of CD-based LED films involves intricate manufacturing techniques. The resulting security risk and high cost restrict the further application of CD-based LEDs. Here, we present a cost-effective method to obtain CD-based LED films via in situ extrusion in a twin-screw extruder. By fine-tuning the extrusion temperature, we created blue-emitting LEDs. The resulting fluorescent films exhibited remarkable stability, retaining 94% fluorescence intensity after 180 days of storage. We also prepared yellow, pure white, and cool white LEDs with malleable shapes, validating the versatility of the in situ extrusion method. More importantly, the manufacturing cost for CD-based films amounts to only about 0.8 RMB/g, which is substantially lower than that of the reported preparation methods. This work offers a cost-effective, safe, and massive approach to preparing photoluminescent LEDs, paving the way for the development of more sustainable and efficient CD-based LEDs. Light-emitting diode ; Materials science ; Extrusion ; Fluorescence ; Luminescence ; Optoelectronics ; Photoluminescence ; Nanotechnology ; Diode ; One-Step ; Chemical engineering ; Composite material ; Optics Carbon and Quantum Dots Applications ; Nanocluster Synthesis and Applications ; Quantum Dots Synthesis And Properties
Authors: Tian Tian | Myuto Kashihara | Weidan Yan | Yasushi Nishihara
Source: ACS Catalysis (article, 2024-07-25)
Field: Chemistry — Organic Chemistry

Palladium-Catalyzed Decarbonylative Nucleophilic Halogenation of Acyl Fluorides and Chlorides: Synthesis of Aryl Halides via Reductive Elimination of the C–X (X = I, Br, and Cl) Bond and Mechanistic Implications Aryl halides are widely recognized as crucial and versatile feedstocks for organic synthesis. However, in palladium-catalyzed reactions, while oxidative addition of carbon–halogen bonds is thermodynamically favorable, the reverse reaction─reductive elimination with the formation of carbon–halogen bonds─poses a significant challenge. As part of conducting a series of decarbonylative transformations of acyl halides, we developed a decarbonylative nucleophilic halogenation of acyl fluorides and chlorides through Pd-mediated reductive elimination of the C–X bond. These reactions enable the synthesis of aryl iodides, bromides, and chlorides using alkali metal halides. Regarding the reaction mechanism, the Xantphos ligand emerges as a crucial factor in promoting reductive elimination, leading to the formation of a stable Pd(0) intermediate and an oxidative adduct trans-(Xantphos)Pd(ArCO)X. Two proposed mechanisms involve Xantphos-promoted outer-sphere nucleophilic substitution and direct transhalogenation between acyl halides and alkali metal halides. In the latter mechanism, acyl fluorides or acyl chlorides react with alkali metal halides to form the corresponding acyl iodides or acyl bromides in situ and under mild conditions through decarbonylation, yielding the desired aryl halides via unimolecular fragment coupling. Importantly, it is evident that controlling the rate of acyl halide formation through the appropriate combination of substrates and alkali metal halides is crucial for the success of this reaction. Indeed, we found that the gradual formation of acyl iodide is pivotal in managing the undesired generation of I2, a known catalyst poison. This observation enables us to fine-tune reaction conditions, thereby improving the selectivity of the desired transformation. As a result, we achieve enhanced yields of the final products and establish more sustainable and robust catalytic processes. This advancement not only boosts the applicability and reliability of our synthetic methodology but also underscores the potential for broader adoption in organic synthesis. Reductive elimination ; Halogenation ; Catalysis ; Chemistry ; Aryl ; Palladium ; Halide ; Nucleophile ; Decarbonylation ; Medicinal chemistry ; Oxidative addition ; Reductive dechlorination ; Organic chemistry ; Alkyl Catalytic C–H Functionalization Methods ; Fluorine in Organic Chemistry ; Sulfur-Based Synthesis Techniques
Authors: Patrick W. Fowler | Cate S. Anstöter
Source: ChemPhysChem (article, 2024-01-27)
Field: Chemistry — Organic Chemistry

Tuning (Anti)Aromaticity: Variations on the [8]‐Circulene Framework Optoelectronic properties of organic molecules are underpinned by delocalisation and delocalisability of π-electrons. These properties are sensitive to small changes in electron count, whether achieved by heteroatom substitution or redox chemistry. One measure of the delocalisability of π-electrons is the current induced by an external magnetic field, which is diagnostic of (anti)aromaticity. The ab initio ipsocentric method is used here to model diverse ring-current patterns in the family of [8]-circulenes based on tetracyclopenta[def,jkl,pqr,vwx]tetraphenylene (TCPTP), in different charge states, with disjoint hetero-atom substitution, and with CC units systematically replaced by BN pairs. Maps calculated at the CHF/CTOCD-DZ2/6-31G** level reveal that these modifications of the TCPTP framework access the full range of possibilities for current from concentric global circulations (typically counter rotating) to full (non-aromatic) localisation. In the ipsocentric approach, induced current density is partitioned into robust orbital contributions that obey selection rules based on orbital symmetry, energy and nodal character. The selection rules are applied here to interpret current-density and exploit insights gained from simpler models to suggest design strategies for fine-tuning of π-delocalisability (aromaticity and antiaromaticity) in macrocyclic frameworks. Aromaticity ; Antiaromaticity ; Chemistry ; Ring (chemistry) ; Ring current ; Ab initio ; Computational chemistry ; Density functional theory ; Chemical physics ; Heteroatom ; Molecule ; Molecular physics ; Physics ; Magnetic field ; Quantum mechanics ; Organic chemistry Synthesis and Properties of Aromatic Compounds ; Luminescence and Fluorescent Materials ; Organoboron and organosilicon chemistry