Article
Materials Science, Multidisciplinary
Nilgoon Irani, Yaswanth Murugesan, Can Ayas, Lucia Nicola
Summary: Discrete dislocation plasticity is a modeling technique that treats plasticity as the collective motion of dislocations, with the core fields affecting edge dislocation interactions. Simulation results show that the influence of core fields is negligible compared to Volterra fields or external loads.
MECHANICS OF MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Yang Dan, Dallas R. Trinkle
Summary: In this study, the atomic energies for isolated screw dislocation cores in Mg were calculated using the first-principles energy density method (EDM). The distribution of atomic energies in the dislocations reflects both the slip in the cores and the elastic energy further away. The line energies were computed by summing up the atomic energies, and from there, the core energies and energy differences were straightforward to determine.
MATERIALS RESEARCH LETTERS
(2022)
Article
Physics, Multidisciplinary
Malik Wagih, Christopher A. Schuh
Summary: The segregation of solute atoms at grain boundaries significantly affects the properties of polycrystals. However, there is a limited understanding of the variations in solute segregation tendencies in different grain boundary microenvironments and a wide range of alloys. This study presents an algorithmic framework that can learn the complete spectrum of solute segregation energies in metal polycrystals without the need for alloy interatomic potentials. It offers a pathway to comprehensively catalog grain boundary solute segregation with quantum accuracy for all alloy compositions.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Tomohito Tsuru, Mitsuhiro Itakura, Masatake Yamaguchi, Chihiro Watanabe, Hiromi Miura
Summary: By using density functional theory calculations, this study investigated the effect of Al and V solutes on dislocation motion in pure titanium and alpha-titanium alloys. It was found that both Al and V solutes reduce stacking fault energy in the basal plane, while Al solute increases stacking fault energy in the prismatic plane. These solutes facilitate dislocation motion in the basal plane by reducing the energy difference between prismatic and basal cores.
COMPUTATIONAL MATERIALS SCIENCE
(2022)
Article
Chemistry, Physical
Daniel Wolverson, Benjamin Smith, Enrico Da Como, Charles Sayers, Gary Wan, Luca Pasquali, Mattia Cattelan
Summary: A simple first-principles approach is used to estimate the core level shifts observed in X-ray photoelectron spectroscopy for the 4f electrons of Hf, Ta, W, and Re. The results show that this approach can provide insights into modifications of the commensurate charge density wave and the surface termination of MXenes.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Multidisciplinary Sciences
Rahul Nikhar, Krzysztof Szalewicz
Summary: Developing theoretical frameworks for predicting new polymorphs is valuable. This study presents an ab initio based force-field approach that significantly speeds up crystal structure prediction compared to fully ab initio schemes. The authors have developed an inexpensive and reliable method for molecular crystal structure predictions. The method starts from a two-dimensional graph of the crystal's monomers and utilizes quantum mechanical calculations to develop an accurate force field for crystal prediction. The robustness of this method has been demonstrated by successfully finding the experimental crystal within the top 20 predicted polymorphs for each molecule investigated.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Yongsheng Zhao, Fengyun Yan, Yi An
Summary: The formation and properties of interfaces in composite materials are crucial for their preparation. This study investigated the adsorption behavior of copper atoms on the (111) surface of H-terminated diamond using first-principles calculations. The results showed that copper adsorption was not sensitive to the diamond surface and the interface formed was a metastable structure.
Article
Chemistry, Physical
Augustin Bussy, Jurg Hutter
Summary: It is found that LR-TDDFT for core level spectroscopy using standard local functionals suffers from errors, and a correction scheme based on many-body perturbation theory is proposed. The correction scheme takes into account self-interaction error and orbital relaxation, improving computational efficiency and yielding corrected spectra in a single calculation.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Ronald L. Kam, KyuJung Jun, Luis Barroso-Luque, Julia H. Yang, Fengyu Xie, Gerbrand Ceder
Summary: This article investigates the phase diagram of the Li2S-P2S5 pseudo-binary system and finds that the superionic conductors in this system are metastable but thermodynamically accessible at room temperature. The vibrational and configurational entropy play crucial roles in the stability of superionic conductors.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
Daniel Duarte Ruiz, Caterina Cocchi
Summary: This study used advanced methods to investigate core spectroscopy in LiCoO2 and CoO2, revealing that excitonic effects play a negligible role in the X-ray absorption spectra of these materials. Monitoring the electronic structure of LiCoO2 during the delithiation process is sufficient to capture the evolution of their X-ray absorption signatures.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Xun Xu, Tingyu Liu, Qiuyue Li
Summary: The study investigates the relative stability and optimal positions of intrinsic defects and Cu defects in LiAlO2 crystal, showing that Cu-Li is most stable in O-rich conditions and energetically preferred under O-poor conditions, leading to the optimum OSL signal. Furthermore, other trapped-hole centers such as Cu-Li-V-Li and STH in the crystal also play a role and need to be considered for overall crystal performance.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
Derek S. Wang, Susanne F. Yelin, Johannes Flick
Summary: This study demonstrates how to tune the optical properties of defects in solid-state materials via the formation of defect polaritons in an optical cavity from first principles. It shows significant polaritonic splitting and absorption intensity enhancement, potentially overcoming phonon-limited single-photon emission from defect centers. These findings are expected to inspire experimental investigations of strong light-matter coupling between defect centers and cavity photons for applications in quantum technologies.
Article
Multidisciplinary Sciences
Jussi Lehtonen
Summary: This article reviews the experiments and concepts presented by Angus Bateman in 1948 regarding sexual selection and the Bateman gradient. The study develops mathematical models showing that asymmetry in gamete numbers alone can generate steeper Bateman gradients in males. The research provides evidence for Bateman's claim about the role of gamete numbers in sexual selection.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Jiali Yao, Zixu Zhang, Dayang Wang, Keke Huang, Wensheng Yang, Litao Sun, Renguo Xie, Narayan Pradhan
Summary: Inorganic and hybrid metal halides have attracted increasing interest due to their diverse structures and properties. Mechanochemistry is considered a universal synthetic approach for their synthesis. The library of metal halides includes various types of compounds, and the structure-property relationships are well revealed. This study provides fundamental guidance for developing new metal halides with selective optoelectronic and magnetic properties.
CHEMISTRY OF MATERIALS
(2023)
Article
Materials Science, Coatings & Films
Yong Han, James W. Evans, Michael C. Tringides
Summary: We analyze the adsorption and intercalation processes of hydrogen on a graphene surface on SiC through first-principles calculations. Our results show that intercalation between the top-layer and buffer-layer graphene is thermodynamically more favorable than adsorption on the top-layer graphene. We also calculate the energy barriers for hydrogen diffusion on and under the graphene layer and assess the penetration capability of hydrogen atoms on the graphene terrace.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Article
Nanoscience & Nanotechnology
Nermine Chaari, David Rodney, Emmanuel Clouet
SCRIPTA MATERIALIA
(2019)
Article
Nanoscience & Nanotechnology
Piotr Kwasniak, Emmanuel Clouet
SCRIPTA MATERIALIA
(2019)
Article
Materials Science, Multidisciplinary
B. Luthi, F. Berthier, L. Ventelon, B. Legrand, D. Rodney, F. Willaime
MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING
(2019)
Article
Materials Science, Multidisciplinary
Piotr Kwasniak, Emmanuel Clouet
Article
Chemistry, Physical
Antoine Kraych, Emmanuel Clouet, Lucile Dezerald, Lisa Ventelon, Francois Willaime, David Rodney
NPJ COMPUTATIONAL MATERIALS
(2019)
Article
Materials Science, Multidisciplinary
Thomas Soyez, Daniel Caillard, Fabien Onimus, Emmanuel Clouet
Article
Materials Science, Multidisciplinary
Emile Maras, Emmanuel Clouet
Summary: The plasticity in hexagonal close-packed zirconium is controlled by screw dislocations, which easily glide in prismatic planes and occasionally across-slip in other planes at high temperatures. Molecular dynamics simulations reveal a combination of prismatic and pyramidal slip in the high stress regime, with basal slip favored at low stress levels due to a change in the glide mechanism.
Article
Materials Science, Multidisciplinary
Baptiste Bienvenu, Lucile Dezerald, David Rodney, Emmanuel Clouet
Summary: This paper presents a yield criterion that can predict the yield stress and active slip systems in bcc transition metals. It is based on ab initio calculations of screw dislocation glide properties and is compared with experimental results, accurately describing the plastic behaviors observed in different metals.
Article
Multidisciplinary Sciences
Daniel Caillard, Baptiste Bienvenu, Emmanuel Clouet
Summary: Crystal strength and plastic flow are controlled by the motion and interaction of dislocations. In body-centred cubic metals, anomalous slip occurs due to the high mobility of multi-junctions, which glide at a much faster velocity compared to single dislocations. Both experiments and atomistic simulations demonstrate that these multi-junctions can be formed under dynamic conditions, contrary to the predictions of elasticity theory in crystals with weak elastic anisotropy like tungsten, explaining the existence of anomalous slip in most body-centred cubic metals.
Article
Materials Science, Multidisciplinary
D. Da Fonseca, F. Onimus, F. Mompiou, M. -C. Marinica, E. de Sonis, E. Clouet, T. Jourdan
Summary: This study investigates the influence of elastic properties of point defects on dislocation climb under stress and irradiation. The elastic dipole tensors and diaelastic polarizabilities of vacancies and self-interstitial atoms in aluminum are evaluated using density functional theory calculations. These parameters are then incorporated into a Monte Carlo code and a diffusion model to estimate the stress dependence of dislocation climb. The results show that both parameters have an influence on point defect absorption under stress, with the dipole tensor effect only being 5 times larger than the polarizability effect. Additionally, considering polarizability is necessary for simulations under applied stress.
Article
Materials Science, Multidisciplinary
Lisa Ventelon, Daniel Caillard, Berengere Luthi, Emmanuel Clouet, David Rodney, Francois Willaime
Summary: We investigate the mobility of screw dislocations decorated by carbon solutes in body-centred cubic iron through density functional theory (DFT) calculations and in-situ straining experiments. We propose a glide mechanism where dislocation glide occurs by the formation and migration of kinks controlled by the jumps of carbon atoms. The validity of the proposed mechanism is supported by the quantitative agreement between experimental measurements and analytical model.
Article
Materials Science, Multidisciplinary
Guillaume Hachet, Lisa Ventelon, Francois Willaime, Emmanuel Clouet
Article
Materials Science, Multidisciplinary
Baptiste Bienvenu, Chu Chun Fu, Emmanuel Clouet
Article
Materials Science, Multidisciplinary
Luis Casillas-Trujillo, Davide Gambino, Lisa Ventelon, Bjorn Alling