Changes in the local structure and magnetic properties at Fe sites due to defects were addressed in a detailed manner in Co2FeAl by 57Fe Mössbauer spectroscopy. Based on the systematic correlation of these results a comprehensive understanding of the defects and hence of the different types of disordering that occur in Co2FeAl subjected to different non-equilibrium treatments have been obtained in this study. As high as 35% of the Fe atoms were deduced to be associated with the A2 type of disordering in Co2FeAl, which provides a basic understanding of the observed much lower value of spin polarization as observed in this system against the high value predicted theoretically. Also this study revealed a striking linear correlation between the valence electron concentration and the effective magnetic hyperfine fields as deduced at different sites of occupation of 57Fe atoms.
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http://dx.doi.org/10.1039/d0cp04572a | DOI Listing |
Sci Total Environ
January 2025
Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan; Isotope Science Center, The University of Tokyo, Bunkyo, Tokyo 113-0032, Japan. Electronic address:
The adsorption reaction on clay minerals is crucial for understanding the environmental behavior of various cations, including cesium (Cs). However, its details remain unclear because of multiple adsorption sites of the clay minerals, a significant difference between concentrations in the atomic-scale experiments and the actual environment, and difficulties of evaluating bonding states of the adsorbed cations. It is expected that systematic experiments at the atomic-scale with a wide concentration range and application of density functional theory (DFT) calculations overcome the problems and bring crucial insights to link laboratory experiment results with environmental sample analysis.
View Article and Find Full Text PDFMol Divers
January 2025
Key Laboratory for Macromolecular Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, People's Republic of China.
Molecular Property Prediction (MPP) is a fundamental task in important research fields such as chemistry, materials, biology, and medicine, where traditional computational chemistry methods based on quantum mechanics often consume substantial time and computing power. In recent years, machine learning has been increasingly used in computational chemistry, in which graph neural networks have shown good performance in molecular property prediction tasks, but they have some limitations in terms of generalizability, interpretability, and certainty. In order to address the above challenges, a Multiscale Molecular Structural Neural Network (MMSNet) is proposed in this paper, which obtains rich multiscale molecular representations through the information fusion between bonded and non-bonded "message passing" structures at the atomic scale and spatial feature information "encoder-decoder" structures at the molecular scale; a multi-level attention mechanism is introduced on the basis of theoretical analysis of molecular mechanics in order to enhance the model's interpretability; the prediction results of MMSNet are used as label values and clustered in the molecular library by the K-NN (K-Nearest Neighbors) algorithm to reverse match the spatial structure of the molecules, and the certainty of the model is quantified by comparing virtual screening results across different K-values.
View Article and Find Full Text PDFAcc Chem Res
January 2025
Institute of Energy: Sustainability, Environment and Equity (I:SEE), State University of New York at Stony Brook, Stony Brook, New York 11794, United States.
ConspectusLithium-ion batteries are recognized as an important electrochemical energy storage technology due to their superior volumetric and gravimetric energy densities. Graphite is widely used as the negative electrode, and its adoption enabled much of the modern portable electronics technology landscape. However, developing markets, such as electric vehicles and grid-scale storage, have increased demands, including higher energy content and a diverse materials supply chain.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Center for Nano Science and Technology, Fondazione Istituto Italiano di Tecnologia, Via R. Rubattino 81 20134 Milan, Italy. Electronic address:
Hypothesis: Interfacial solvation forces arise from the organisation of liquid molecules near solid surfaces. They are crucial to fundamental phenomena, spanning materials science, molecular biology, and technological applications, yet their molecular details remain poorly understood. Achieving a complete understanding requires imaging techniques, such as three-dimensional atomic force microscopy (3D AFM), to provide atomically resolved images of solid-liquid interfaces (SLIs).
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Center for Electron Microscopy, South China University of Technology, Guangzhou 511436, China.
Adsorption behaviors are typically examined through adsorption isotherms, which measure the average adsorption amount as a function of partial pressure or time. However, this method is incapable of identifying inhomogeneities across the adsorbent, which may occur in the presence of strong intermolecular interactions of the adsorbate. In this study, we visualize the adsorption of molecular iodine (I) in the metal-organic framework material MFM-300(Sc) using high-resolution scanning transmission electron microscopy (STEM).
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