Structural Stability and Thermal Transformation of Pt-Sn Bimetallic Nano Clusters

2010 ◽  
Vol 12 ◽  
pp. 131-138 ◽  
Author(s):  
H.B. Liu ◽  
Jorge Antonio Ascencio
Keyword(s):  
Solid Solution ◽  
Structural Stability ◽  
Density Functional ◽  
Surface Segregation ◽  
Thermal Transformation ◽  
Heating Process ◽  
Embedded Atom Method ◽  
Elemental Distribution ◽  
Embedded Atom ◽  
Modified Embedded Atom Method

In this work, structural stability and thermal transformation of Pt-Sn bimetallic nano clusters are studied by molecular dynamics simulations, combined with the modified embedded atom method. For a more accurate description of the interatomic interactions, new Modified Embedded Atom Method alloying parameters for Pt-Sn are derived based on ab initio density functional theory calculations. The calculated Gibbs free energies of formation show that all kinds of structures are energetically favorable and the most stable structure is solid solution cluster, and then the core/shell, and eutectic-like cluster. For whatever compositions the eutectic-like clusters must transform into one pure Sn cluster and one Pt core/Sn shell cluster up to certain temperature during heating process, the Sn coverage on Pt core is dependent on its composition. For solid solution and Pt core/Sn shell or Sn core/Pt shell, once the structure forms, it can keep basically unchanged from the point of view of elemental distribution. Surface segregation is not apparent observed.

Atomistic Simulations of fcc Pt75Ni25 and Pt75Re25 Cubo-octahedral Nanoparticles

2004 ◽  
Vol 818 ◽  
Author(s):  
Guofeng Wang ◽  
M.A. Van Hove ◽  
P.N. Ross ◽  
M.I. Baskes
Keyword(s):  
Sandwich Structure ◽  
Surface Segregation ◽  
Atomistic Simulations ◽  
Embedded Atom Method ◽  
Interatomic Potentials ◽  
Atomic Shell ◽  
Embedded Atom ◽  
The Monte Carlo Method ◽  
Equilibrium Structures ◽  
Modified Embedded Atom Method

AbstractWe have developed interatomic potentials for Pt-Ni and Pt-Re alloys within the modified embedded atom method (MEAM). Furthermore, we applied these potentials to study the equilibrium structures of Pt75Ni25 and Pt75Re25 nanoparticles at T=600 K using the Monte Carlo method. In this work, the nanoparticles are assumed to have disordered fcc cubo-octahedral shapes (terminated by {111} and {100} facets) and contain from 586 to 4033 atoms (corresponding to a diameter from 2.5 to 5 nm). It was found that, due to surface segregation, (1) the Pt75Ni25 nanoparticles form a surface-sandwich structure: the Pt atoms are enriched in the outermost and third atomic shells, while the Ni atoms are enriched in the second atomic shell; (2) the equilibrium Pt75Re25 nanoparticles adopt a core-shell structure: a Pt-enriched shell surrounding a Pt-deficient core.

Surface segregation in Pt25Rh75 alloys studied by Monte Carlo simulations and the modified embedded atom method

2007 ◽  
Vol 601 (7) ◽  
pp. 1668-1676 ◽  
Author(s):  
Jan Luyten ◽  
Maarten Schurmans ◽  
Claude Creemers ◽  
Bouke S. Bunnik ◽  
Gert Jan Kramer
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Surface Segregation ◽  
Embedded Atom Method ◽  
Embedded Atom ◽  
Modified Embedded Atom Method

scholarly journals Atomistic Simulations of Pure Tin Based on a New Modified Embedded-Atom Method Interatomic Potential

Metals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 900 ◽  
Author(s):  
Won-Seok Ko ◽  
Dong-Hyun Kim ◽  
Yong-Jai Kwon ◽  
Min Lee
Keyword(s):  
Density Functional ◽  
Nearest Neighbor ◽  
Interatomic Potential ◽  
Free Energy Calculations ◽  
Embedded Atom Method ◽  
Force Matching ◽  
Embedded Atom ◽  
Β Phase ◽  
Diffusion Phenomena ◽  
Modified Embedded Atom Method

A new interatomic potential for the pure tin (Sn) system is developed on the basis of the second-nearest-neighbor modified embedded-atom-method formalism. The potential parameters were optimized based on the force-matching method utilizing the density functional theory (DFT) database of energies and forces of atomic configurations under various conditions. The developed potential significantly improves the reproducibility of many fundamental physical properties compared to previously reported modified embedded-atom method (MEAM) potentials, especially properties of the β phase that is stable at the ambient condition. Subsequent free energy calculations based on the quasiharmonic approximation and molecular-dynamics simulations verify that the developed potential can be successfully applied to study the allotropic phase transformation between α and β phases and diffusion phenomena of pure tin.

Construction of modified embedded atom method potentials for Cu, Pt and Cu–Pt and modelling surface segregation in Cu3Pt alloys

2007 ◽  
Vol 601 (14) ◽  
pp. 2952-2961 ◽  
Author(s):  
Jan Luyten ◽  
Maarten Schurmans ◽  
Claude Creemers ◽  
Bouke S. Bunnik ◽  
Gert Jan Kramer
Keyword(s):  
Surface Segregation ◽  
Embedded Atom Method ◽  
Embedded Atom ◽  
Modified Embedded Atom Method

Classical Interatomic Potential for Nb-Alumina Interfaces

2000 ◽  
Vol 654 ◽  
Author(s):  
K. Albe ◽  
R. Benedek ◽  
D. N. Seidman ◽  
R.S. Averback
Keyword(s):  
Density Functional ◽  
Large Scale ◽  
Interatomic Potential ◽  
Local Density ◽  
Embedded Atom Method ◽  
Metal Interface ◽  
Functional Theory ◽  
Embedded Atom ◽  
Local Density Functional Theory ◽  
Modified Embedded Atom Method

AbstractA modified-embedded-atom-method (MEAM) potential is derived for the ternary system Al-O-Nb in order to simulate the model oxide-metal interface sapphire-niobium. In the present work, MEAM parameters for Al and O given by Baskes were adopted, and the parameters for Nb are adjusted to match experimental data for pure Nb and calculated properties for Nb oxides and aluminides. The properties for niobium oxides and aluminides were obtained from local- density-functional-theory (LDFT) calculations. The resultant potential was tested in simulations for the Nb(111)/α -alumina(0001) interface. MEAM predictions of the work of separation and the interlayer relaxations for two interface terminations are in excellent agreement with LDFT calculations. The MEAM potential therefore appears suitable for large-scale computer simulation of oxide-metal interface properties.

scholarly journals Atomistic simulations of Ag–Cu–Sn alloys based on a new modified embedded-atom method interatomic potential

2021 ◽  
Author(s):  
Won-Seok Ko ◽  
Jung Soo Lee ◽  
Dong-Hyun Kim
Keyword(s):  
Density Functional ◽  
Binary Systems ◽  
Interatomic Potential ◽  
Atomic Scale ◽  
Atomistic Simulations ◽  
Embedded Atom Method ◽  
Material System ◽  
Embedded Atom ◽  
Modified Embedded Atom Method ◽  
Potential Parameters

AbstractAn interatomic potential for the ternary Ag–Cu–Sn system, an important material system related to the applications of lead-free solders, is developed on the basis of the second nearest-neighbor modified embedded-atom-method formalism. Potential parameters for the ternary and related binary systems are determined based on the recently improved unary description of pure Sn and the present improvements to the unary descriptions of pure Ag and Cu. To ensure the sufficient performance of atomistic simulations in various applications, the optimization of potential parameters is conducted based on the force-matching method that utilizes density functional theory predictions of energies and forces on various atomic configurations. We validate that the developed interatomic potential exhibits sufficient accuracy and transferability to various physical properties of pure metals, intermetallic compounds, solid solutions, and liquid solutions. The proposed interatomic potential can be straightforwardly used in future studies to investigate atomic-scale phenomena in soldering applications. Graphical abstract

Surface segregation in CuPt alloys by means of an improved modified embedded atom method

2007 ◽  
Vol 76 (17) ◽  
Author(s):  
M. Schurmans ◽  
J. Luyten ◽  
C. Creemers ◽  
R. Declerck ◽  
M. Waroquier
Keyword(s):  
Surface Segregation ◽  
Embedded Atom Method ◽  
Embedded Atom ◽  
Modified Embedded Atom Method
Sign in / Sign up

Export Citation Format

Share Document