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Machine learned interatomic potentials using random features

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npj Computational Materials 2022年第1期8卷 48-57页

作者： Gurjot Dhaliwal Prasanth B.Nair Chandra Veer Singh Department of Mechanical and Industrial Engineering University of Toronto5 King’s College RdTorontoM5S 3G8ONCanada Institute for Aerospace Studies University of Toronto4925 Dufferin StTorontoM3H 5T6ONCanada Department of Materials Science and Engineering University of Toronto184 College StTorontoM5S 3E4ONCanada

We present a method to model interatomic interactions such as energy and forces in a computationally efficient *** proposed model approximates the energy/forces using a linear combination of random features,thereby enabling fast parameter estimation by solving a linear least-squares *** discuss how random features based on stationary and non-stationary kernels can be used for energy approximation and provide results for three classes of materials,namely two-dimensional materials,metals and *** and energy predictions made using the proposed method are in close agreement with density functional theory calculations,with training time that is 96%lower than standard kernel *** Dynamics calculations using random features based interatomic potentials are shown to agree well with experimental and density functional theory *** frequencies as computed by random features based interatomic potentials are within 0.1%of the density functional theory ***,the proposed random features-based potential addresses scalability issues encountered in this class of machine learning problems.

关键词： random stationary interatomic

Statistical Modeling of the Influence of Electron Degeneracy on the interatomic Interactions

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Journal of Modern Physics 2010年第3期1卷 171-174页

作者： Anatoly M. Dolgonosov 不详

It is shown that electrons forming simple and multiple covalent bonds may have different contribu-tions to the interatomic interactions due to the degeneracy of electron states. A simple relationship between the lengt... 详细信息

关键词： interatomic Interactions Covalent Bond Degeneracy of Electron States Theory of Generalized Charges Bond Length Ratio

Energetics and diffusion of point defects in Au/Ag metals:A molecular dynamics study

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Chinese Physics B 2019年第8期28卷 95-104页

作者： Zhi-Yong Liu Bin He Xin Qu Li-Bo Niu Ru-Song Li Fei Wang Xi’an High Technology Institute

To reveal the potential aging mechanism for self-irradiation in Pu-Ga alloy,we choose Au-Ag alloy as its substitutional material in terms of its mass density and lattice *** a first step for understanding the microscopic behavior of point defects in Au-Ag alloy,we perform a molecular dynamics(MD)simulation on energetics and diffusion of point defects in Au and Ag *** results indicate that the octahedral self-interstitial atom(SIA)is more stable than the tetrahedral *** stability sequence of point defects for He atom in Au/Ag is:substitutional site>octahedral interstitial site>tetrahedral interstitial *** He-V cluster(Hen Vm,V denotes vacancy)is the most stable at n=*** the mono-vacancy diffusion,the MD calculation shows that the first nearest neighbour(1 NN)site is the most favorable site on the basis of the nudged elastic band(NEB)calculation,which is in agreement with previous experimental *** are two peaks for the second nearest neighbour(2 NN)and the third nearest neighbour(3 NN)diffusion curve in octahedral interstitial site for He atom,indicating that the 2 NN and 3 NN diffusion for octahedral SIA would undergo an intermediate defect structure similar to the 1 NN *** 3 NN diffusion for the tetrahedral SIA and He atom would undergo an intermediate site in analogy to its initial *** diffusion of point defects,the vacancy,SIA,He atom and He-V cluster may have an analogous effect on the diffusion velocity in Ag.

关键词： interatomic potential radiation damage point defect diffusion barrier

Atomistic simulation study of favored compositions of Ni-Nb-Al metallic glasses

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Science China(Technological Sciences) 2018年第12期61卷 1829-1838页

作者： CAI Bei YANG MengHao LIU JianBo LI JiaHao LIU BaiXin Key Laboratory of Advanced Materials(MOE) School of Materials science and Engineering Tsinghua University

This study investigates the formation process of Ni-Nb-Al metallic glasses. To this end, a long-range n-body potential was constructed for the Ni-Nb-Al ternary metal system, and applied to atomistic simulations. The simulations not only showed the physical origins of the amorphous phase formation, but also quantitatively predicted a hexagonal compositional region that energetically favors the glass formation. The energy difference between the solid solution and metallic glass, which generates the amorphization driving force(ADF), was suggested to indicate the glass-formation ability(GFA) of each alloy. Based on the computed ADFs, the Ni55 Nb25 Al20 alloy exhibited the highest GFA among the Ni-Nb-Al members, implying that the glass formed by this amorphous alloy is more thermodynamically stable than other alloys in the system. In a Voronoi tessellation analysis, the knee point of the coordination-number distribution curve corresponded to the glass-formation region of the Ni-NbAl system.

关键词： interatomic potential atomistic simulation glass-formation ability Ni-Nb-Al system

A descriptor of “material genes”: Effective atomic size in structural unit of ionic crystals

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Science China(Technological Sciences) 2019年第5期62卷 849-855页

作者： CHEN Dong LI ShunNing JIE JianShu LI SiBai ZHENG ShiSheng WENG MouYi YU ChangCheng LI ShuCheng CHEN DaJun PAN Feng School of Advanced Materials Shenzhen Graduate School Peking University

The atomic size of each element, described by the ionic radius, is one category of "material genes" and can facilitate our understanding of atomic arrangements in compounds. Most of the ionic radii currently used to measure the sizes of cations and anions in ionic crystals are derived from hard-sphere model based on the coordination numbers, or the soft-sphere model incorporating the effect of ionic polarization. Herein we take a first step towards a novel "effective atomic size"(EAS) model,which takes into consideration the impact of the types and number of neighboring atoms on the relationship between ionic radii and interatomic distances. Taking the binary compounds between Group IA/IIA and VIA/VIIA elements gathered from the latest databases as an example, we show that the proposed EAS model can yield excellent agreement between the predicted and the DFT-calculated interatomic distances, with deviation of less than 0.1 ?. A set of EAS radii for ionic crystals has been compiled and the role of coordination numbers, geometric symmetry and distortion of structural units has been examined. Thanks to its superior predictability, the EAS model can serve as a foundation to analyze the structure of newly-discovered compounds and to accelerate materials screening processes in the future works.

关键词： ionic radii interatomic distance effective atomic size coordination environment structural units

The dielectric and dynamical properties of zinc-blende BN,AlN and GaN from first-principle calculation

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Science China(Physics,Mechanics & Astronomy) 2008年第8期51卷 1037-1045页

作者： WANG HuanYou XU Hui ZHANG NingDan ZHANG PengHua Department of Physics Central South UniversityChangsha 410083China Department of Physics Xiangnan UniversityChenzhou 423000China

The ab initio calculations of the electronic structural,dielectric and lattice-dy namical properties of zinc-blende BN,AlN and GaN were presented. The ground-state properties,i.e.,the lattice constant,the bulk modulus and band gap,were calculated using a plane-wave-pseudopotential method within the density-function theory. A linear-response approach to the density-function perturb theory was used to derive the Born effective charge,the high-frequency dielectric constants and interatomic force constants for these materials. The interatomic force contants(IFCs) are useful for interpolating the dynamical matrices through the whole Brillouin zone. Phonon frequencies along high-symmetry lines were also obtained by interpolating the dynamical matrices using the interatomic force constants. In this paper,we discussed the difference of dielectric and dynamical properties among zinc-blende BN,AlN and GaN,and meanwhile,also compared these properties with other experimental data available and theoretical values. Generally,the calculations were in good agreement with the other existing experimental data and theoretical values.

关键词： first principle dielectric constant Born effective charge interatomic force constant phonon band structure

Theoretical Study of the Rare Earth Compounds Lafe<sub>13-X</sub>t<sub>x</sub>(T= Cr, Cu, Ga, Mn, Ni) and Curie Temperature Variation

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Materials Sciences and Applications 2011年第8期2卷 1166-1174页

作者： Lingping Xiao Jiang Shen Jiangxi Blue Sky University Nanchang 330098 PR China

The phase stability and site preference of the intermetallics LaFe13-xTx (T=Cr, Cu, Ga, Mn, Ni) with NaZn13-type structure have been investigated by lattice inversion potentials. The calculated results indicate that each of the stabilizing elements Cr and Mn significantly decreases the cohesive energy of LaFe13-xTx and plays a role in stabilizing the 1:13 structure. The calculated lattice parameters of LaFe13-xTx (T=Al, Si) compounds are in good agreement with the experimental data. Qualitative analyses are carried out on the behavior of the Curie temperature and magnetocrystalline anisotropy. All the results indicate that the pair potentials based on the lattice inversion method can effectively give a deeper insight into the structure and property of complex materials.

关键词： Rare Earth Compounds interatomic Potentials Site Preference Computers Simulation.