Molecular Dynamics Simulation of the Elastic Deformation of Nanometer Diameter Metal Clusters

1994 ◽  
Vol 332 ◽  
Author(s):  
Dilip Y. Paithankar ◽  
Julian Talbot ◽  
Ronald P. Andres
Keyword(s):  
Elastic Deformation ◽  
Bulk Material ◽  
Gold Clusters ◽  
Dynamics Simulation ◽  
Embedded Atom Method ◽  
Static Compression ◽  
Deformation Curves ◽  
Octahedral Clusters ◽  
Embedded Atom ◽  
Eam Potential

ABSTRACTIndentation using the AFM is a powerful method for determining elastic properties of small supported clusters. However, a theoretical framework has yet to be developed to interpret such measurements. The elastic deformation of nanometer sized gold clusters are modeled using the Embedded Atom Method (EAM) potential of Foiles et al. [1]. Force versus deformation curves are obtained for a series of truncated octahedral clusters having FCC symmetry (N=38, 201, 586, 1289, 2406). It is found that the MD results both for static compression and for harmonic vibration can be analytically estimated by using an elastic constant for the clusters analogous to the elastic modulus of a bulk material. However MD predictions for static compression are not in agreement with the deformation results of Schaefer et al. [2].

Monte Carlo Simulation for Structure of Metallic Clusters

2010 ◽  
Author(s):  
Y. H. Park ◽  
I. Hijazi
Keyword(s):  
Monte Carlo ◽  
Empirical Studies ◽  
Gold Clusters ◽  
Structural Motif ◽  
Pentagonal Bipyramid ◽  
Embedded Atom Method ◽  
Embedded Atom ◽  
The Monte Carlo Method ◽  
Monte Carlo Simulated Annealing ◽  
Eam Potential

The structural stability and energetics for small copper and gold clusters Cun and Aun (n = 21–56) were investigated using an effective Monte Carlo simulated annealing method, which employs the Aggregate-Volume-Bias Monte Carlo (AVBMC) algorithm. Incorporated in the Monte Carlo method, is an efficient Embedded Atom Method (EAM) potential developed by the authors. In general agreement with previous empirical studies, the lowest-energy copper structures adapt a single icosahedral structural motif, with pentagonal bipyramid geometry as the building block. However, contrary to studies that describe gold as less symmetric, this work demonstrates that gold clusters adapt both an icosahedral and icositetrahedral structural motifs with many clusters having symmetric geometries.

Molecular Dynamics Simulation of Sputtering with Mmany-Body Interactions

1988 ◽  
Vol 100 ◽  
Author(s):  
Davy Y. Lo ◽  
Tom A. Tombrello ◽  
Mark H. Shapiro ◽  
Don E. Harrison
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulation ◽  
Single Crystal ◽  
Low Energy ◽  
Dynamics Simulation ◽  
Embedded Atom Method ◽  
Many Body ◽  
Embedded Atom ◽  
Dynamics Simulations ◽  
Small Single Crystal

ABSTRACTMany-body forces obtained by the Embedded-Atom Method (EAM) [41 are incorporated into the description of low energy collisions and surface ejection processes in molecular dynamics simulations of sputtering from metal targets. Bombardments of small, single crystal Cu targets (400–500 atoms) in three different orientations ({100}, {110}, {111}) by 5 keV Ar+ ions have been simulated. The results are compared to simulations using purely pair-wise additive interactions. Significant differences in the spectra of ejected atoms are found.

ATOMISTIC SCALE SIMULATION OF TEXTURED SURFACES ON DRY SLIDING FRICTION

2013 ◽  
Vol 37 (3) ◽  
pp. 927-936 ◽  
Author(s):  
Ming-Yuan Chen ◽  
Zheng-Han Hong ◽  
Te-Hua Fang ◽  
Shao-Hui Kang ◽  
Li-Min Kuo
Keyword(s):  
Sliding Friction ◽  
Surface Texturing ◽  
Dynamics Simulation ◽  
Embedded Atom Method ◽  
Textured Surface ◽  
Textured Surfaces ◽  
Many Body ◽  
Embedded Atom ◽  
Modified Embedded Atom Method ◽  
Body Potential

Fe sliding on a Fe substrate with surface texturing is investigated using molecular dynamics simulation. The modified embedded-atom method many-body potential is used to describe the interaction of Fe atoms. The tribological properties of surface texturing during nanosliding are discussed. Results indicate that a textured surface has lower friction than that of a flat surface. In addition, a surface with parallel grooves has lower friction than that of a dimpled surface. Hence, surface texturing greatly affects friction.

Non-Equilibrium Molecular Dynamics Simulation of the Rapid Solidification of Metals

1989 ◽  
Vol 159 ◽  
Author(s):  
Cliff F. Richardson ◽  
Paulette Clancy
Keyword(s):  
Molecular Dynamics ◽  
Picosecond Laser ◽  
Simulation Method ◽  
Dynamics Simulation ◽  
Embedded Atom Method ◽  
Embedded Atom ◽  
Non Equilibrium Molecular Dynamics ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
Non Equilibrium

ABSTRACTThe ultra-rapid melting and subsequent resolidification of Embedded Atom Method models of the fcc metals copper and gold are followed using a Non-Equilibrium Molecular Dynamics computer simulation method. Results for the resolidification of an exposed (100) face of copper at room temperature are in good agreement with recent experiments using a picosecond laser. At T = 0.5 Tm, the morphology of the solid/liquid interface is shown to be similar to a Lennard-Jones model. The morphology of the crystal-vapor interface at 92% of Tm shows a significant disordering of the topmost layers. Difficulties with the EAM model for gold are observed. Comparison of the Baskes et al. and Oh and Johnson embedding functions are discussed.

The Infidence of Defect Concentrations on Migration Energies in AgZn Alloys

1988 ◽  
Vol 128 ◽  
Author(s):  
T. D. Andreadis ◽  
M. Rosen ◽  
J. M. Eridon ◽  
D. J. Rosen
Keyword(s):  
Linear Approximation ◽  
Embedded Atom Method ◽  
Local Defect ◽  
Migration Energy ◽  
New Model ◽  
Impurity Atoms ◽  
Embedded Atom ◽  
Defect Reactions ◽  
Eam Potential ◽  
Formation Energies

ABSTRACTMigration energies in Ag of vacancies, interstitials, Zn impurity atoms, interstitial-iipurity cumplexes, and vacancy-impurity complexes were calculated using Embedded Atom. Method (EAM) potentials in Molecular Statics calculations. A new Zn EAM potential was determined and used in these calculations. The dependence of the migration energies on local defect concentrations was determined in a linear approximation. Binding and formation energies of defects are also presented. A new model for the migration energy appropriate for defect reactions is introduced.

INFLUENCE OF PRESSURE AND ATOMIC CONCENTRATION ON STRUCTURE AND MECHANICAL PROPERTIES OF CuNi ALLOY BY MOLECULAR DYNAMICS SIMULATION

2020 ◽  
Vol 65 (6) ◽  
pp. 54-60
Author(s):  
Thao Nguyen Thi ◽  
Hang Trinh Thi Thu
Keyword(s):  
Mechanical Properties ◽  
Dynamics Simulation ◽  
Embedded Atom Method ◽  
Face Centered Cubic ◽  
Atomic Concentration ◽  
Common Neighbor ◽  
Hexagonal Close Packed ◽  
Embedded Atom ◽  
The Common ◽  
Face Centered

The structure and mechanical properties of Cu80Ni20 and Cu50Ni50 alloys with the size of 4000 atoms have been investigated using molecular dynamic (MD) simulation. The interactions between atoms of the system were calculated by the Sutton-Chen type of embedded atom method. Using a cooling rate of 0.01 K\ps, we find that both Ni and Cu atoms are crystallized into face centered cubic (fcc) and the hexagonal close packed (hcp) phases when the sample was cooled down to 300 K. The atomic concentration of CuNi alloy samples have a different effect on this crystallization. The transformation to the crystalline phase is analyzed through the Common Neighbor Analysis (CNA) methods. Furthermore, we focus on the dependence of the mechanical properties of CuNi alloy on pressure and atomic concentration

Molecular Dynamics Simulation of Compressive Mechanical Behavior of Nanocrystalline Fe

2005 ◽  
Vol 475-479 ◽  
pp. 3291-3294
Author(s):  
Shi Fang Xiao ◽  
Yu Hu Wang
Keyword(s):  
Mechanical Properties ◽  
Molecular Dynamics ◽  
Plastic Deformation ◽  
Deformation Process ◽  
Dynamics Simulation ◽  
Embedded Atom Method ◽  
Deformation Region ◽  
Embedded Atom ◽  
Boundary Atom ◽  
Strain Strengthening

The uniaxial compressive mechanical properties of nanocrystalline Fe are simulated with a molecular dynamics technique and the analytical embedded-atom method. An asymmetrical mechanical phenomenon between tensile and compressive process is found, and the yield stress and flow stress in compression are higher than those in tension simulations. The compressive deformation process can be described as three characteristic regions: quasi-elastic deformation, plastic flowing deformation, and strain strengthening. During the plastic flowing deformation region, the material shows very good compressive ductibility. The plastic deformation is mainly dominated by the grain boundary atom slide.

An embedded-atom-method study of diffusion of an Ag adatom on (111) Ag

1990 ◽  
Vol 68 (9) ◽  
pp. 1035-1040 ◽  
Author(s):  
W. K. Rilling ◽  
C. M. Gilmore ◽  
T. D. Andreadis ◽  
J. A. Sprague
Keyword(s):  
Activation Energy ◽  
Saddle Point ◽  
Surface Diffusion ◽  
Minimum Energy ◽  
Dynamics Simulation ◽  
Embedded Atom Method ◽  
Fixed Position ◽  
Embedded Atom ◽  
Minimization Procedure ◽  
Gradient Energy

The activation energy, vibrational frequency, and surface-diffusion jumps of a single adatom on a perfect (111) surface were studied using the embedded-atom method. The activation energy was determined with a conjugate gradient energy-minimization procedure. The surface adatom was moved in steps across the (111) plane through a saddle point. The adatom position was fixed within (parallel to) the (111) plane; but, the Ag adatom was free to relax, normal to the (111) plane. In this way the adatom was free to ride up over the saddle point; so that at each fixed position within the (111) plane the Ag adatom was free to move to its minimum energy. Also all of the atoms within the Ag crystal were free to relax to minimum-energy positions as the Ag adatom was moved across the surface. The minimum activation energy calculated for adatom diffusion was 0.058 eV. The embedded-atom method was also combined with a molecular dynamics simulation to observe the vibrations of the surface atoms and the adatom and to observe surface-diffusion jumps of the adatom. The adatom jumped to new surface sites at a frequency of approximately 1 × 1012 jumps s−1 at a temperature of 700 K.

Atomistic Study of the Mechanical Properties of One-Dimensional Nanomaterials

2005 ◽  
Vol 901 ◽  
Author(s):  
Kazuhito Shintani ◽  
Shunji Kameoka ◽  
Shuhei Sato ◽  
Yusuke Kometani
Keyword(s):  
Mechanical Properties ◽  
Cross Sections ◽  
Dynamics Simulation ◽  
Embedded Atom Method ◽  
One Dimensional ◽  
Embedded Atom ◽  
Young’S Moduli ◽  
Modified Embedded Atom Method ◽  
Au Nanowires ◽  
Atomistic Study

AbstractThe mechanical properties of Au nanowires under a uniaxial load are investigated by molecular-dynamics simulation. The modified embedded-atom method (MEAM) potential is employed to calculate the interactions between Au atoms. Ten kinds of model nanowires with different cross-sections and axis directions are prepaired. The structural dependence and size effect of the Young’s moduli of Au nanowires are discussed.

scholarly journals A numerical fitting procedure for the embedded atom method interatomic potential and a bridged finite element-molecular dynamics method for large atomic systems

2021 ◽  
Author(s):  
Karthik Narayan
Keyword(s):  
Molecular Dynamics ◽  
Md Simulation ◽  
Embedded Atom Method ◽  
Discretization Scheme ◽  
Element Discretization ◽  
Atomic Systems ◽  
Embedded Atom ◽  
Fitting Procedure ◽  
Numerical Fitting ◽  
Eam Potential

This thesis presents a powerful numerical fitting procedure for generating Embedded Atom Method (EAM) inter-atomic potentials for pure Face Centred Cubic (FCC) and Body Centred Cubic (BCC) metals. The numerical fitting procedure involves assuming a reasonable parameterized form for a portion of the EAM potential, and then fitting the remaining portion to select thermal and elastic properties of the metal. Molecular Dynamics (MD) simulation is used to effect the fitting procedure. The procedure is used to generate an EAM potential for copper, an FCC metal. This resulting EAM potential is used to conduct MD simulations of perfect copper crystals containing voids of different geometries. Following this, a bridged Finite Element-Molecular Dynamics (FE-MD) method is presented, which can be used to simulate large atomic systems much more efficiently than MD simulation alone. The method implements a novel element discretization scheme proposed by the author that is so general that it can be applied to any system of objects interacting with each other via any potential (simple or complex, EAM or otherwise). This bridged FE-MD method is used to reanalyze the voids in the copper crystal lattice. The resulting virial stress increment patterns are found to agree remarkably with the earlier MD simulation results. Furthermore, the bridged FE-MD method is much quicker than the pure MD simulation. These two facts prove the power and usefulness of the bridged FE-MD method, and validate the proposed element discretization scheme

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