Article
Chemistry, Physical
Jiteng Zhang, Na Jin, Lixian Lian, Zhinan Cao, Dengming Zhuang
Summary: The TiO/V interface is a potential nucleation site for He bubbles in vanadium alloys, where TiO precipitation promotes the formation of monovacancies and enhances the attractive interaction between He atoms and monovacancies. Furthermore, He atoms can be persistently captured in both monovacancy and multi-vacancy clusters, suggesting a strong thermodynamic preference for He trapping at these defects.
APPLIED SURFACE SCIENCE
(2021)
Article
Nuclear Science & Technology
Fan Jia, Yiren Wang, Yong Jiang
Summary: In this study, the mechanical properties and helium behaviors in YAlO3 (YAH) strengthened Ni-based ODS alloys were assessed using first-principles calculations. The results indicate that YAH shows elastic deformation compatibility with the matrix and can capture dispersed helium atoms, inhibiting the formation of helium bubbles and preventing helium-induced embrittlement.
NUCLEAR MATERIALS AND ENERGY
(2022)
Article
Materials Science, Multidisciplinary
ShuLong Wen, XingMing Zhang, HuiQiu Deng, Min Pan
Summary: This study investigates the stability of the W/Y2O3 interface, as well as the behavior of helium (He) near the interface, using first-principles calculations. The results show that the termination structures of the interface greatly affect its stability, with the OW-terminated interface being more stable than the YW-terminated interface under certain conditions. The study also demonstrates that the W/Y2O3 interface acts as a strong trap for capturing He from the W layer, but has difficulty capturing He from the YO layer. Additionally, the study explores the effect of strain on the dissolution of He in W and Y2O3, finding that strain caused by lattice matching is the primary factor influencing the solution of He near the interface. The findings provide theoretical support for understanding the phase interface effects on He behavior in Y2O3 dispersion-strengthened W.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Ryosuke Jinnouchi, Ferenc Karsai, Carla Verdi, Georg Kresse
Summary: In this study, a machine learning aided molecular dynamics method is proposed to evaluate the hydration free energy of atoms and molecules adsorbed at liquid-solid interfaces. The calculated hydration free energies indicate that only the hydroxyl group adsorbed on the Pt(111) surface attains a hydration stabilization, which is attributed to differences in the adsorption site and surface morphology.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Jingyi Zhang, Huanglong Li
Summary: This study comprehensively investigates the atomic structures and band alignment properties of Bi2O2Se:Bi2O5Se interfaces with different configurations of the interfacial anion layers. The correlation between band offset and interfacial atom intermixing is observed and rationalized, while the detrimental effect of oxygen vacancies on the interface is also identified.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Chemistry, Physical
Li Sun
Summary: The adhesion energy, interfacial energy, interfacial fracture toughness, electronic structure, and valence bond of the Fe3O4 (001)/FeCr2O4 (001) interface were studied using first principles density functional method. Among 12 interface models with different terminal combinations, Model E composed of Fe3O4 (001) - FeO termination/FeCr2O4 (001) - Fe termination showed the maximum adhesion work and highest interfacial fracture toughness, making it the most stable thermodynamically. The electronic structure revealed the presence of ionic covalent and metallic bonds at the interface.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Physics, Multidisciplinary
Yan-Mei Jing, Shao-Song Huang
Summary: The study systematically investigated the atomic behaviors of point defects and helium atoms at the Fe(110)-graphene interface through first principles calculations, revealing a strong interaction between graphene and the Fe substrate. The Fe(110)-graphene interface was found to act as a strong sink for trapping defects, suggesting potential applications in tolerating radiation damage.
Article
Nuclear Science & Technology
Yiren Wang, Fan Jia, Yong Jiang
Summary: Oxide-dispersion-strengthened nickel alloys with Hf additions are expected to have high temperature mechanical properties and durable helium resistance. First-principles density functional theory calculations were used to evaluate the energetic and charge density behaviors of helium in the alloy system. The presence of Y2Hf2O7 oxide in the nickel matrix can significantly reduce the formation of helium bubbles, with the helium atoms preferring to occupy the interfacial and octahedral sites of the oxide. The high diffusion barrier of helium in Y2Hf2O7 is attributed to the strong hybridization between interstitial helium and neighboring oxygen orbitals.
NUCLEAR ENGINEERING AND TECHNOLOGY
(2023)
Article
Chemistry, Physical
Raquel Yanes-Rodriguez, Adriana Cabrera-Ramirez, Rita Prosmiti
Summary: In this study, the stability and interactions of specific clathrate hydrates are investigated by first-principles computations. The results show that both He@sI and He@sII clathrate hydrates are stable under the given conditions, with He@sII being the most energetically favorable.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Xi Yan, Friederike Wrobel, I-Cheng Tung, Hua Zhou, Hawoong Hong, Fanny Rodolakis, Anand Bhattacharya, Jessica L. McChesney, Dillon D. Fong
Summary: In this study, the atomic and electronic structures of the SrTiO3 (001) surface were monitored using in situ techniques. It was observed that a 2D electron gas (2DEG) disappears and reappears after the completion of each SrO and TiO2 monolayer, respectively. The presence of a TiO2 double layer and vacancies within the layer contribute to the generation of a surface potential and mobile electrons, explaining this phenomenon. This finding provides insights into the complex oxide interfaces and facilitates atomic-scale defect engineering in oxide electronics.
ADVANCED MATERIALS
(2022)
Article
Geochemistry & Geophysics
Luis E. Gonzalez, David J. Gonzalez
Summary: We studied the evolution of liquid Fe's structural and dynamic properties under different pressures using ab-initio molecular dynamics technique. The calculated static structure matches well with experimental data, indicating the presence of a local icosahedral short-range order in the liquid. The dynamic structure reveals two modes for all pressures, which can be related to the double-peak structure in the Fourier spectra of velocity autocorrelation functions. Our findings also show the existence of transverse acoustic excitation modes and changes in the electronic density of states with increasing pressure. Transport coefficients like self-diffusion, shear viscosity, and adiabatic sound velocity are compared with experimental data.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2023)
Article
Nanoscience & Nanotechnology
Kaihui Ma, Qinghui Wu, Panshuai Ma, Lingxiao Bai, Jian Xu
Summary: Metal growth is crucial for the efficiency and performance of processes in materials manufacturing or applications. This study focuses on the poorly understood growth of metal during oxygen removal from its oxides. The role of stress release in the formation of iron whiskers is investigated, and the superior stress release capabilities of hydrogen compared to carbon monoxide are emphasized. The development of a larger-sized nanoscale hole structure effectively inhibits the growth of whiskers.
SCRIPTA MATERIALIA
(2024)
Article
Materials Science, Multidisciplinary
Er-kang Liu, Qi Wang, Zhi-hong Guo, Li-jun Wang, Xi-wang Chang, Ya-xu Zheng, Chen-yu Ma, Zhen-ye Chen, Bo Wang, Li-guang Zhu
Summary: In this paper, the nucleation and growth mechanisms of ferrite on Mg-Ti-oxide inclusions were investigated using first-principles calculations and solid-state pressure bonding experiments. The results showed that the formation of cation vacancies is the limiting step for Mn solute atom absorption by Mg-Ti-oxides. The experimental results demonstrated that MgTiO3 with the maximum Mn-depleted zone width is the most effective for ferrite nucleation, consistent with the calculation results.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Multidisciplinary Sciences
M. Monira, M. A. Helal, M. N. H. Liton, M. Kamruzzaman, S. Kojima
Summary: The cubic phase of CsNbO3 perovskite has been studied using first-principles method to investigate its elastic, electronic, photocatalytic, and optical properties for various technological applications. The effects of pressure on structural stability have been confirmed through computed elastic constants. The material's high elastic moduli, hardness, and toughness suggest its potential application in industrial machinery design. The material exhibits a ductile to brittle transition at 20 GPa and has an indirect bandgap suitable for photovoltaic and IR photodetector applications. The study also analyzes the contribution of individual atomic orbitals to band formation and characterizes the bonding and electron charge density distribution.
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Multidisciplinary
Zu-Da He, Wen-Ce Li, Jin-Long Yang, Hua-Kai Xu, Xiang-Fu Xu, Guo-Xia Lai, You-Da Che, Wei-Ling Zhu, Xiao-Dong Yang, Xing-Yuan Chen
Summary: This paper investigates the optical and ferroelectric properties of R3c-CuNbO3 and the effects of strain on these properties through first-principles calculations. The results show that R3c-CuNbO3 has a moderate band gap and efficient absorption of visible light. The Cu-O and Nb-O bond interactions are crucial for the photovoltaic properties of CuNbO3. Under compressive conditions, the photoelectric conversion efficiency of CuNbO3 is significantly improved. By modulating the compressive strain, CuNbO3 is expected to be an excellent ferroelectric photovoltaic material.
Article
Multidisciplinary Sciences
Erik Fransson, Mattias Slabanja, Paul Erhart, Goran Wahnstrom
Summary: The perturbative treatments of lattice dynamics are limited for strongly anharmonic systems, metastable crystal structures, and liquids. Molecular dynamics simulations using correlation functions can provide access to the full dynamics of these systems, including dynamical structure factors that bridge the gap to experiment. The dynasor package is a flexible and efficient tool that simplifies the analysis of correlation functions, handling input from major MD packages and allowing for easy extension to support additional codes.
ADVANCED THEORY AND SIMULATIONS
(2021)
Article
Chemistry, Physical
Jakub Fojt, Tuomas P. Rossi, Tomasz J. Antosiewicz, Mikael Kuisma, Paul Erhart
Summary: This study demonstrates a subsystem approach that accurately predicts the optical spectra of nanoparticle-molecule assemblies with good computational efficiency, and can be extended to larger systems.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Rina Ibragimova, Paul Erhart, Patrick Rinke, Hannu-Pekka Komsa
Summary: This study explores the distribution and composition of surface functional groups on different MXenes using a multiscale computational approach. It shows that mixtures of functional groups are favorable on all studied MXene surfaces and that the distribution of functional groups is largely independent of the type of metal, carbon, or nitrogen species and/or number of atomic layers in the MXene. Some properties strongly depend on surface composition, while others exhibit only weak dependence.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Martin Gren, Erik Fransson, Mattias Angqvist, Paul Erhart, Goran Wahnstrom
Summary: Transition metal carbides, such as tungsten carbide, exhibit high hardness, high melting points, and low chemical reactivity. This study focuses on the high-temperature thermodynamic properties of tungsten carbide, investigating the different crystal structures at varying temperatures and their relevance for industrial applications. The research utilizes first-principles density-functional theory to model the behavior of tungsten carbide phases, providing insights into their stability and phase transitions.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
J. Magnus Rahm, Joakim Lofgren, Erik Fransson, Paul Erhart
Summary: Research on the thermodynamics of hydrogen in Pd-Au using alloy cluster expansions investigates the impact of different chemical orderings on material behavior, with a focus on hydrogen absorption/desorption isotherms. Results indicate the formation of a long-range ordered L1(2) phase and the occurrence of phase separation when full equilibrium is reached in the presence of hydrogen. These findings shed light on the stability of absorption/desorption isotherms in Pd-Au over time.
Article
Chemistry, Physical
Joakim Brorsson, Yifei Zhang, Anders E. C. Palmqvist, Paul Erhart
Summary: By combining first-principles calculations, atomistic simulations, and experimental measurements, the connection between chemical ordering and physical properties in inorganic clathrates has been revealed. An order-disorder transition in the quaternary clathrate series was discovered, leading to discontinuity in heat capacity and explaining the unusual temperature dependence of Seebeck coefficient and electrical conductivity. It is suggested that this phenomenon may not be limited to specific materials but could be observed in a wide range of inorganic clathrates and materials with chemical ordering on sublattices.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Physical
Pernilla Ekborg-Tanner, Paul Erhart
Summary: The study examines the behavior of surface alloys AuPd and CuPd in various H environments, utilizing simulations and thermodynamic analysis to determine H coverage and surface composition. Differences in segregation of Cu and Pd on the surface at different H coverages were observed in the two alloys, indicating complexity in the enrichment and depletion of Cu under different H coverages.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Nanoscience & Nanotechnology
Joakim Brorsson, Anders E. C. Palmqvist, Paul Erhart
Summary: The study used a combination of theoretical and computational simulation methods to explore compositions with high power factors in clathrates, considering cost factors. The results showed that cost-effective performance can be achieved by reducing the number of Al and Ga atoms, while using extrinsic dopants.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Multidisciplinary Sciences
Joakim Brorsson, Arsalan Hashemi, Zheyong Fan, Erik Fransson, Fredrik Eriksson, Tapio Ala-Nissila, Arkady Krasheninnikov, Hannu-Pekka Komsa, Paul Erhart
Summary: High-order force constant expansions, combined with GPU-accelerated molecular dynamics simulations, provide an accurate, transferable, and efficient approach for sampling the dynamical properties of materials.
ADVANCED THEORY AND SIMULATIONS
(2022)
Article
Nanoscience & Nanotechnology
Mikael Kuisma, Benjamin Rousseaux, Krzysztof M. Czajkowski, Tuomas P. Rossi, Timur Shegai, Paul Erhart, Tomasz J. Antosiewicz
Summary: Ultrastrong coupling refers to a unique mode of interaction between light and matter, where the coupling strength is comparable to the resonance energy of the cavity or emitter. Traditional approximations to quantum optical Hamiltonians fail in the ultrastrong coupling regime, as the ground state of the coupled system obtains photonic characteristics, resulting in changes in ground-state energy. Using time-dependent density functional theory calculations, we demonstrate that a single organic molecule can achieve ultrastrong coupling with a plasmonic dimer comprising of a few hundred atoms. The ultrastrong coupling leads to significant modifications in ground-state energy, accounting for a considerable portion of the total interaction energy.
Article
Nanoscience & Nanotechnology
Pernilla Ekborg-Tanner, J. Magnus Rahm, Victor Rosendal, Maria Bancerek, Tuomas P. Rossi, Tomasz J. Antosiewicz, Paul Erhart
Summary: This study utilized a multiscale modeling approach to determine optimal conditions for optical hydrogen sensing using the Pd-Au-H system, and observed the pattern of optical sensitivity changing with hydrogen concentration at the single nanoparticle level. While alloy composition has limited impact, it strongly affects hydrogen uptake and thermodynamic sensitivity.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Christopher Linderaelv, J. Magnus Rahm, Paul Erhart
Summary: Alloying can tune the properties of transition metal dichalcogenide (TMD) monolayers. This study investigates the phase diagrams and mixing behavior of 72 TMD monolayer alloys through first-principles calculations and alloy cluster expansions. It is found that ordered phases are generally absent at room temperature, but certain alloys exhibit a stable Janus phase. Additionally, the band edge positions of some alloys can be continuously tuned within the range set by the boundary phases.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Jakub Fojt, Tuomas P. Rossi, Mikael Kuisma, Paul Erhart
Summary: This study models the generation of hot carriers across the interface between plasmonic nanoparticles and a CO molecule, finding that the hot electron transfer probability depends on the distance, energetic alignment, and excitation frequency, while hot hole transfer is limited to shorter distances. The hybridization of molecular orbitals is the key predictor for hot carrier transfer.
Editorial Material
Chemistry, Physical
Paul Erhart, J. Magnus Rahm
Summary: This apparent mathematical quirk utilizes symmetry to resolve the issue of determining the equilibrium shape of asymmetrical terminations in two-dimensional materials crystals.
Article
Materials Science, Multidisciplinary
Christopher Linderalv, Witlef Wieczorek, Paul Erhart
Summary: Through first-principles calculations and the generating function method, the coupling of specific defects to vibrational degrees of freedom has been systematically elucidated, serving as a guide for identifying optically active defects in h-BN. This detailed theoretical study provides important guidance for photonic-based quantum technologies in h-BN.
