jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Roberta Siqueira Soldaini Oliveira | Marco Aurélio Souza Oliveira | Itamar Borges
Source: ChemRxiv (preprint, 2024-12-20)
Field: Chemistry — Organic Chemistry

A NEW AROMATICITY DESCRIPTOR BASED ON ELECTRON DELOCALIZATION EMPLOYING THE DISTRIBUTED MULTIPOLE ANALYSIS (DMA) Aromatic compounds are energetically stable and have low reactivity, but an aromaticity concept is difficult to establish because it cannot be measured. For this reason, different descriptors have been developed to rationalize and quantify this phenomenon. Given that cyclic electron delocalization is an essential property of aromatic compounds, in this work, we propose six new aromatic descriptors based on Stone's distributed multipole analysis (DMA) to partition the molecular electron density on electric multipoles localized on different sites of a molecule. The new aromatic descriptors are based on different components of DMA quadrupole electric moment tensor Q_2, the first term of the DMA multipole expansion having contributions from the out-of-plane electron density. The proposed descriptors are straightforward to obtain because the DMA method is implemented on different popular electronic structure packages. For users of Gaussian, the formatted checkpoint with the calculated molecular electron density is used as input for the GDMA2 program of Stone to compute the necessary Q_2 components. The computer protocol for computing the Q_2-based descriptors in either way is presented. To assess the performance of the aromaticity descriptors, we used 12 tests of the Girona benchmark developed by the Solà group involving different distortions of benzene, substitutions, complexation, ring size dependence, atom size dependence, heteroatomic species, Clar systems, and fulvenes. The correct aromaticity trends of the six new indices were predicted entirely in 78% of the cases; for 16%, most trends were predicted and only failed utterly in 6%. The failed cases were related to the appreciable contribution of in-plane sigma electrons. Our proposal joins others to contribute to understanding the important and complex chemical concept of aromaticity. Aromaticity ; Electron delocalization ; Multipole expansion ; Delocalized electron ; Electron ; Computational chemistry ; Chemistry ; Physics ; Quantum mechanics ; Organic chemistry ; Molecule Synthesis and Properties of Aromatic Compounds ; Graph theory and applications ; Molecular spectroscopy and chirality
Authors: You Li | Xiaolong Zhang | Hui Li
Source: ChemRxiv (preprint, 2024-12-17)
Field: Materials Science — Materials Chemistry

Employing the active learning strategy to construct full-dimensional intermolecular potential energy surfaces within spectroscopic accuracy In this work, we employed an uncertainty-driven active learning strategy to achieve highly efficient point sampling for full-dimension potential energy surface constructions. The model uncertainty is defined as the weighted square energy difference between two neural network (NN) models trained with the same dataset, and the local maximums of uncertainty would be added into the training set by two criteria. A two-step sampling procedure was introduced to reduce the computational costs of expansive double-precision neural network training. The 6-D H$_2$O-He system was chosen as the test system. A reference PES was constructed firstly by the newly developed MLRNet model with a weighted RMSE of 0.028 cm$^{-1}$, where the full-dimension long-range function was fitted by a pruned basis expansion method. Our tests demonstrate that it is also reliable for the long-range switched fundamental invariant neural network (LS-FI-NN) to construct spectroscopically accurate PES, however, it is less inefficient for the newly developed MLRNet model. For the first single-precision sampling, the LS-FI-NN only requires 472 fitting points to achieve a weighted-RMSE of 0.3253 cm$^{-1}$ for 47945 test points. In comparison, the MLRNet requires 652 points to reach a similar accuracy. Notably, the MLRNet demonstrated lower training errors across all sampling cycles and lower test errors in the first few cycles with less trainable parameters, which indicates its potential with an appropriate sampling procedure. For the second double-precision sampling, the LS-FI-NN achieved a test RMSD of 0.0710 cm$^{-1}$ with only 613 points, while the MLRNet can't converge to a given threshold for tens of iterations. The spectroscopic calculations were performed to further validate the accuracy of these PESs. The energy levels of the double precision LS-FI-NN showed great agreement with the reference PES's results, with only 0.0161 cm$^{-1}$ and 0.0044 cm$^{-1}$ average errors for vibrational levels and the band origin shifts. Artificial neural network ; Sampling (signal processing) ; Dimension (graph theory) ; Range (aeronautics) ; Mean squared error ; Test set ; Algorithm ; Computer science ; Energy (signal processing) ; Radial basis function ; Mathematics ; Mathematical optimization ; Artificial intelligence ; Statistics Machine Learning in Materials Science ; Spectroscopy and Quantum Chemical Studies ; Mass Spectrometry Techniques and Applications
Authors: Weilin Zhang
Source: Science and Technology of Engineering Chemistry and Environmental Protection (article, 2024-12-31)
Field: Chemistry — Organic Chemistry

Application status and development trend of two-photon polymerization technology in 3D printing field Two-photon polymerization (TPP) technology has garnered significant attention in the field of 3D printing due to its exceptional sub-micron resolution capabilities. This paper provides a comprehensive overview of the fundamental principles of TPP, material development, system construction, and explores its applications in micro-optics, biomedicine, and micro-electromechanical systems (MEMS). Additionally, this study analyses the technological challenges and future development directions, highlighting the importance of material innovation and interdisciplinary integration. The findings suggest that TPP technology holds immense potential in the field of high-precision manufacturing. Polymerization ; Field (mathematics) ; 3D printing ; Materials science ; Nanotechnology ; Composite material ; Mathematics ; Polymer Photopolymerization techniques and applications
Authors: Yao Luo | Dhruv Desai | Chang, Benjamin K. | Jinsoo Park | Marco Bernardi
Source: arXiv (Cornell University) (preprint, 2024-01-21)
Field: Materials Science — Materials Chemistry

Data-driven compression of electron-phonon interactions First-principles calculations of electron interactions in materials have seen rapid progress in recent years, with electron-phonon (e-ph) interactions being a prime example. However, these techniques use large matrices encoding the interactions on dense momentum grids, which reduces computational efficiency and obscures interpretability. For e-ph interactions, existing interpolation techniques leverage locality in real space, but the high dimensionality of the data remains a bottleneck to balance cost and accuracy. Here we show an efficient way to compress e-ph interactions based on singular value decomposition (SVD), a widely used matrix / image compression technique. Leveraging (un)constrained SVD methods, we accurately predict material properties related to e-ph interactions - including charge mobility, spin relaxation times, band renormalization, and superconducting critical temperature - while using only a small fraction (1-2%) of the interaction data. These findings unveil the hidden low-dimensional nature of e-ph interactions. Furthermore, they accelerate state-of-the-art first-principles e-ph calculations by about two orders of magnitudes without sacrificing accuracy. Our Pareto-optimal parametrization of e-ph interactions can be readily generalized to electron-electron and electron-defect interactions, as well as to other couplings, advancing quantitative studies of condensed matter. Singular value decomposition ; Statistical physics ; Curse of dimensionality ; Electron ; Leverage (statistics) ; Renormalization ; Bottleneck ; Computer science ; Interpolation (computer graphics) ; Physics ; Chemistry ; Computational physics ; Algorithm ; Quantum mechanics ; Artificial intelligence Machine Learning in Materials Science ; Magnetic and transport properties of perovskites and related materials ; Physics of Superconductivity and Magnetism
Authors: A.A. Okhlopkova | Н. Н. Лазарева | Yu. V. Kapitonova | P. N. Tarasova | A. P. Vasilev | S. N. Danilova | R. V. Borisova
Source: Polymer materials and technologies (article, 2024-01-01)
Field: Materials Science — General Materials Science

POLYMER-SILICATE COMPOSITES BASED ON POLYTETRAFLUOROETHYLENE (REVIEW) - , Polytetrafluoroethylene ; Silicate ; Composite material ; Polymer ; Materials science ; Polymer science ; Chemical engineering ; Engineering Material Properties and Applications ; Advanced Theoretical and Applied Studies in Material Sciences and Geometry ; Silicone and Siloxane Chemistry
Authors: M.K. Hasan | Mehmet Ali Üstüner | Haluk Korucu | Mohammad Ruhul Amin Bhuiyan | Hayati Mamur
Source: GAZI UNIVERSITY JOURNAL OF SCIENCE (article, 2024-07-23)
Field: Materials Science — Materials Chemistry

Influence of Leg Geometry on the Performance of Bi2Te3 Thermoelectric Generators This study analyzed the significant performance using COMSOL Multiphysics software of thermoelectric modules (TEMs) fabricated from aluminium oxide (Al2O3), copper (Cu), and bismuth telluride (Bi2Te3) materials, with a particular focus on investigating various leg geometries. The TEM design had Al2O3 for insulation, Cu for conducting, and Bi2Te3 for TE legs among the Cu. Investigated the influence of square and rectangular TE legs with heights of 2.0, 2.75, and 3.5 mm on critical parameters such as the normalized current density, electric potential, temperature gradient, and total internal energy within the TEM. Furthermore, the impact of varying thicknesses in the insulator and conductor layers of the TEM was explored. The results consistently demonstrated that the square leg geometry, particularly when configured with a height of 2.75 mm, outperformed other leg geometries. Consequently, it is suggested to adopt a square-shaped Bi2Te3 TEM measuring 1 mm × 1 mm × 2.75 mm with a 0.50 mm Al2O3 thickness and 0.125 mm Cu thickness during the manufacturing process. Investigate how temperature differences in TE device leg design are influenced by parameters such as the Seebeck coefficient (S), thermal conductivity (k), and electrical conductivity (σ). At lower temperatures, modeling reveals lower electrical conductivity and enhanced thermal conductivity, highlighting the significance of S = ± 2.37×10⁻⁴ V/K. This illustrates the high potential of TEM for applications in thermoelectric generator (TEG) manufacturing. Bismuth telluride ; Multiphysics ; Materials science ; Thermoelectric effect ; Thermoelectric generator ; Thermal conductivity ; Seebeck coefficient ; Electrical resistivity and conductivity ; Thermoelectric materials ; Geometry ; Conductor ; Composite material ; Finite element method ; Electrical engineering ; Thermodynamics ; Physics ; Mathematics Advanced Thermoelectric Materials and Devices ; Thermal Radiation and Cooling Technologies ; Thermal properties of materials
Authors: Florian Knoop | Nimrod Benshalom | Matan Menahem | P. Gärtner | Tommaso Salzillo | Omer Yaffe | Olle Hellman
Source: arXiv (Cornell University) (preprint, 2024-12-23)
Field: Materials Science — Materials Chemistry

Ab initio theory of the non-resonant Raman effect in crystals at finite temperature in comparison to experiment: The examples of GaN and BaZrS3 We present an ab initio theory of the non-resonant Raman scattering process in crystals at finite temperature in direct comparison with experiments. The theory incorporates the scattering geometry and polarization dependence of the Raman process and the small but finite wave vectors of the phonons for correctly describing the scattering with longitudinal optical (LO) modes in optically anisotropic solids. We implement the theory for first-order Raman scattering and showcase the approach for wurtzite Gallium Nitride and the complex chalcogenide perovskite BaZrS3 in comparison to experiment. We subsequently discuss several common estimates for second-order Raman scattering in complex materials, and highlight similarities and differences to established theoretical approaches and simulation protocols both from phonon theory and molecular dynamics. Ab initio ; Raman spectroscopy ; Materials science ; Condensed matter physics ; Molecular physics ; Computational physics ; Quantum mechanics ; Physics Solid-state spectroscopy and crystallography
Authors: Duvalier Madrid-Úsuga | Omar J. Suárez
Source: arXiv (Cornell University) (preprint, 2024-07-11)
Field: Materials Science — Polymers and Plastics

Physical-chemical Approach for the Impact of Modifying Molecular Bridges of TPA-Based Systems to Improve the Photovoltaic Properties of Organic Solar Cells The theoretical design of donor chromophores based on triphenylamine and 2-(1,1-dicyanomethylene)rhodanine (\textbf{DCRD-DCRD-2}) is proposed through structural adaptation with several molecular bridges derived from thiophene that can be used as new organic materials for organic solar cells (OSC). The optoelectronics properties and geometries of the \textbf{DCRD-DCRD-2} organic molecules are characterized using the B3LYP and CAM-B3LYP functional, with the basis set 6-31G(d,p). Consequently, the UV-Visible results revealed that a good relationship was found between the experimental values and the calculated using the DFT and TD-DFT level of theory. The study involved the prediction of photo-physical descriptors such as frontier molecular orbitals, ionization potential, electron affinity, molecular electrostatic potential, reorganization energy, open circuit voltage ($V_{oc}$), fill factor (FF), and short-circuit current ($J_{sc}$) in the ground state geometry, using the B3LYP/6-31G(d,p) basis set. Structural tailoring with various molecular bridges resulted in a narrowing of the energy gap (2.130--1.96eV) with broader absorption spectra (525.55--417.69 nm). An effective charge transfer toward the lowest unoccupied molecular orbitals (LUMO) from the highest occupied molecular orbitals (HOMO) was studied, which played a crucial role in conducting materials. \textbf{DCRD-2} exhibited $λ_{max}$ at $417.69$~nm in EtOH (ethanol) solvent with the lowest band gap (1.96 eV) and the lowest excitation energy of 2.968 eV. The highest mobility of holes and electrons is determined in all the designed molecules due to their low reorganization energy values that validated preferable photovoltaic properties in the \textbf{DCRD-1} molecular system. Photovoltaic system ; Organic solar cell ; Materials science ; Engineering physics ; Process engineering ; Biochemical engineering ; Nanotechnology ; Engineering ; Electrical engineering Conducting polymers and applications ; Organic Electronics and Photovoltaics
Authors: 宣英 宦 | Zeming Hou | Yuzhao Qi | Qiu Xu | Songjiang Xu | Shikai Ma | Dongmei Bao | Daohai Zhang | Guoyong Zhou | Yupeng Zhang | Zhu Wen
Source: Research Square (preprint, 2024-03-18)
Field: Materials Science — Polymers and Plastics

Synergistic flame retardant behavior and mechanism of based on DOPS/triazine-trione groups flame retardants in epoxy resins Abstract Epoxy resin (EP), as a widely used polymer material, is inherently flammable. Bestowing it with high-efficiency flame-retardant properties has always been the focus of attention. Herein, Using triallyl isocyanurate (TAIC) and 9,10-dihydro-9-oxa-10-phospha phenanthrene-10-sulfide (DOPS) as raw materials, a novel bismaleimide flame retardant, tris(3-(9,10-dihydro-9-oxa-0-phosphaphenanthrene-10-sulfide)-propyl)triazine-2,4,6-trione(DOPS-TAIC), was synthesized via a one-step method. Before curing, the structure was characterized using FT-IR, 1 H NMR, and 31 P NMR. Subsequently, the flame retardant DOPS-TAIC was applied to EP, and a series of testing methods were employed to investigate the effects of DOPS-TAIC on the thermal stability, flame retardancy, and mechanical properties of EP. Furthermore, the flame retardant mechanism of DOPS-TAIC in the gas phase and condensed phase was further explored. The results showed that EP/DOPS-TAIC achieved UL-94 V-0 rating with an LOI value of 31.6% when added at 12.5 wt%. In addition, the total heat release (THR), peak heat release rate (PHRR), and average heat release rate (av-HRR) of EP/DOPS-TAIC-12.5 wt% were significantly reduced by 35.05%, 61.83%, and 51.68%, respectively. The SEM-EDS results indicate that DOPS-TAIC can form a more complete and dense char layer, with a higher phosphorus content in the char layer. Meanwhile, TG-IR and Py-GC/MS demonstrate its radical quenching effect in the gas phase, indicating that DOPS-TAIC possesses both condensed-phase and gas-phase flame-retardant mechanisms. Therefore, this study provides a simple and effective method for developing flame-retardant epoxy resins. Fire retardant ; Epoxy ; Triazine ; Materials science ; Composite material ; Polymer chemistry Flame retardant materials and properties ; Epoxy Resin Curing Processes ; Synthesis and properties of polymers
Authors: Ravi Kant Vishwakarma
Source: International Journal of Pharmaceutical Science and Medicine. (review, 2024-03-25)
Field: Chemistry — Analytical Chemistry

ADVANCEMENTS IN UV-SPECTROSCOPY TECHNIQUES FOR SIMULTANEOUS QUANTIFICATION IN PHARMACEUTICAL FORMULATIONS: A SYSTEMATIC REVIEW The simplicity, sensitivity, and cost-effectiveness of UV-spectroscopy have made it a major player in pharmaceutical analysis in recent years.Modern UV-spectroscopy methods developed for simultaneous quantification in pharmaceutical formulations are the focus of this systematic review, which seeks to provide a thorough overview of these developments.In order to provide light on significant trends and issues faced by the discipline, the study thoroughly examines advancements in instrumentation, technique, and practical applications.Highlighting developments in automation capabilities, sensitivity, and resolution, it delves into the evolution of UV-spectrophotometer instruments.The use of chemometrics and multivariate analytic methods to enable simultaneous quantification is the primary focus of the methodological breakthroughs examined.In addition, the paper explores practical uses of ultraviolet (UV) spectroscopy in the pharmaceutical industry, including examples of case studies of API and excipient quantification in different dosage forms.Also covered are the complexities of method validation and sample matrix effects, two of the limits and inherent constraints of UV-spectroscopy.Lastly, the study provides valuable insights into future prospects, touching on possible developments and developing technologies that might change the way pharmaceutical analysis uses UV-spectroscopy. Spectroscopy ; Materials science ; Biochemical engineering ; Nanotechnology ; Chemistry ; Chromatography ; Engineering ; Physics Spectroscopy and Chemometric Analyses ; Analytical Methods in Pharmaceuticals ; Analytical Chemistry and Chromatography
Authors: Liqi Kang | Banghao Wu | Bingxin Zhou | Pan Tan | Yun Kang | Yongzhen Yan | Yi Zong | Shuang Li | Zhuo Liu | Hong Liang
Source: bioRxiv (Cold Spring Harbor Laboratory) (preprint, 2024-09-08)
Field: Chemistry — Spectroscopy

AI-enabled Alkaline-resistant Evolution of Protein to Apply in Mass Production Abstract Artificial intelligence (AI) models have been used to study the compositional regularities of proteins in nature, enabling it to assist in protein design to improve the efficiency of protein engineering and reduce manufacturing cost. However, in industrial settings, proteins are often required to work in extreme environments where they are relatively scarce or even non-existent in nature. Since such proteins are almost absent in the training datasets, it is uncertain whether AI model possesses the capability of evolving the protein to adapt extreme conditions. Antibodies are crucial components of affinity chromatography, and they are hoped to remain active at the extreme environments where most proteins cannot tolerate. In this study, we applied an advanced large language model (LLM), the Pro-PRIME model, to improve the alkali resistance of a representative antibody, a VHH antibody capable of binding to growth hormone. Through two rounds of design, we ensured that the selected mutant has enhanced functionality, including higher thermal stability, extreme pH resistance and stronger affinity, thereby validating the generalized capability of the LLM in meeting specific demands. To the best of our knowledge, this is the first LLM-designed protein product, which is successfully applied in mass production. Production (economics) ; Chemistry ; Economics ; Microeconomics Advanced Proteomics Techniques and Applications ; Bacteriophages and microbial interactions ; Enzyme Structure and Function
Authors: Qian Chang | Ethan Stanifer | Zhan Ma | Binbin Luo | Chang Liu | Lehan Yao | Wenxiao Pan | Xiaoming Mao | Qian Chen
Source: arXiv (Cornell University) (preprint, 2024-03-22)
Field: Materials Science — Materials Chemistry

Nanoscale Imaging of Phonons and Reconfiguration in Topologically-Engineered, Self-Assembled Nanoparticle Lattice Topologically-engineered mechanical frames are important model constructs for architecture, machine mechanisms, and metamaterials. Despite significant advances in macroscopically fashioned frames, realization and phonon imaging of nanoframes have remained challenging. Here we extend for the first time the principles of topologically-engineered mechanical frames to lattices self-assembled from nanoparticles. Liquid-phase transmission electron microscopy images the vibrations of nanoparticles in self-assembled Maxwell and hexagonal lattices at the nanometer resolution, measuring a series of otherwise inaccessible properties such as phonon spectra and nonlinear lattice deformation paths. These properties are experimentally modulated by ionic strength, captured by our discrete mechanical model considering the complexity of nanoscale interactions and thermal fluctuations. The experiment-theory integration bridges mechanical metamaterials and colloidal self-assembly, opening new opportunities to manufacture phononic devices with solution processibility, transformability, light weight, and emergent functions, at underexplored length, frequency, and energy scales. Nanoscopic scale ; Control reconfiguration ; Materials science ; Nanoparticle ; Phonon ; Nanotechnology ; Lattice (music) ; Condensed matter physics ; Physics ; Computer science Anodic Oxide Films and Nanostructures ; Advanced Electron Microscopy Techniques and Applications
Authors: Bálint Kaszás | Péter Nagy | Jenõ Gubicza
Source: SoftwareX (article, 2024-09-01)
Field: Materials Science — Materials Chemistry

DifFault: Simulation of diffraction patterns of faulted crystals We have developed a software library called DifFault to generate X-ray diffraction (XRD) patterns of cubic structures. The simulation of the XRD peak profiles in the patterns is based on physical principles and accounts for the effects of crystallite size, dislocations, and planar faults. The program is able to calculate XRD spectra for any user-defined combination of the microstructural parameters. The presented software library can be integrated easily into modern and efficient numerical libraries such as SciPy and PyTorch. Therefore, the program can be used either in XRD pattern-fitting methods or in the creation of training sets of XRD spectra for machine learning-based prediction of the parameters of the microstructure. Diffraction ; Crystallography ; Computer science ; Materials science ; Geology ; Physics ; Optics ; Chemistry X-ray Diffraction in Crystallography ; Microstructure and Mechanical Properties of Steels ; Microstructure and mechanical properties