MD Potential Files: Difference between revisions

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==Potential Problems With Potentials==
==Potential Types==
This table contains information about the potentials use in MD++.


{| class="wikitable" cellpadding="2"
These are some potential files we used in our simulations of molecular structures. Please note that since we use a variety of codes, the potential files will be in a variety of foremats. The most common codes used by our group are LAMMPS ( and ParaDyne) and MD++. These codes use different file formats for EAM potentials, so all files should specify which file format. We will also try to provide a reference describing the potential.
|-
! Name of Potential || executable || Types of Materials
|-
| Molecular Dynamics || md_$(SYS) || empty potential, for visualization and atom manipulation
|-
| Finnis-Sinclair || fs_$(SYS) || BCC metals (Mo, Ta, W, ...)
|-
| Embedded Atom Method || eam_$(SYS) || FCC metals (Cu, Au, ...)
|-
| Aluminum Glue || alglue_$(SYS) || Al (FCC metal)
|-
| Modified Embedded Atom Method || meam_$(SYS) || FCC metals, BCC metals, semiconductors
|-
| Lennard-Jones || lj_$(SYS) || Noble gas (Ar, ...)
|-
| Stillinger-Webber || sw_$(SYS) || Semiconductors (Si, Ge, C)
|-
| Tersoff || tersoff_$(SYS) || Semiconductors (Si, Ge, C), PRB '''39''' 5566 (1989)
|-
| Tersoff88 || tersoff88_$(SYS) || Si(B) - PRB '''37''' 6991 (1988), Si(C) - PRB '''38''' 9902 (1988) In default, the parameters are set to Si(C). The parameters can be reset to Si(B) by modifying source code, "tersoff88.cpp".
|-
| Brenner || brenner_$(SYS) || C, hydrocarbons
|}


==Relation between the parameters in SW potential and in MD++ codes ==
==Potentials==


The parameters in SW potential model and in MD++ codes are associated, following the rules described in table below. When changing values of the parameters in MD++ codes, make sure you know what you are changing and how.
[[media:eamdata_aufoiles.txt‎ | EAM Foiles potential for Gold - MD++ format.]]

{| class="wikitable" cellpadding="2"
|-
! Parameters in Balamane et al (PRB 46 2250) || Parameters in original SW (PRB 31 5262) || Variables in MD++
|-
| A_1 || = ε*A*B*σ^p || bb = A_1/aa = B*σ^(p-q)
|-
| A_2 || = ε*A*σ^q || = aa
|-
| Z || = ε*λ || = plam
|-
| μ || = σ || = pss
|-
| α || = γ || pgam = γ*pss
|-
| R_c || = a*σ || = acut
|-
| λ_1 || = p || = rho
|-
| λ_2 || = q || Not Used (0)
|}

=="Potential" Problems==

These are some potential files we used in our simulations of molecular structures. Please note that since we use a variety of codes, the potential files will be in a variety of formats. The most common codes used by our group are LAMMPS ( and ParaDyne) and MD++. These codes use different file formats for EAM potentials, so all files should specify which file format. We will also try to provide a reference describing the potential.

==Potential Files==

===MD++ Files===

[[media:eamdata_aufoiles.txt‎ | EAM Foiles potential for Gold.]]
Ref: Park, H. S., Zimmerman J. A., Modeling inelasticity and failure in gold nanowires. Phys. Rev. B 72, 054106 (2005).
Ref: Park, H. S., Zimmerman J. A., Modeling inelasticity and failure in gold nanowires. Phys. Rev. B 72, 054106 (2005).

[[media:eamdata_cufoiles.txt‎ | EAM Foiles potential for Copper.]]
Ref: Aubry, S. and Hughes, D. A., Reductions in stacking fault widths in fcc crystals: Semiempirical calculations. Phys. Rev. B 73, 224116 (2006).

===LAMMPS SET Files ===

[[media:cufoiles_set.txt‎ | EAM Foiles potential for Copper.]]
Ref: Aubry, S. and Hughes, D. A., Reductions in stacking fault widths in fcc crystals: Semiempirical calculations. Phys. Rev. B 73, 224116 (2006).

===LAMMPS FUNC Files===

Latest revision as of 15:17, 10 January 2014

Potential Types[edit]

This table contains information about the potentials use in MD++.

Name of Potential executable Types of Materials
Molecular Dynamics md_$(SYS) empty potential, for visualization and atom manipulation
Finnis-Sinclair fs_$(SYS) BCC metals (Mo, Ta, W, ...)
Embedded Atom Method eam_$(SYS) FCC metals (Cu, Au, ...)
Aluminum Glue alglue_$(SYS) Al (FCC metal)
Modified Embedded Atom Method meam_$(SYS) FCC metals, BCC metals, semiconductors
Lennard-Jones lj_$(SYS) Noble gas (Ar, ...)
Stillinger-Webber sw_$(SYS) Semiconductors (Si, Ge, C)
Tersoff tersoff_$(SYS) Semiconductors (Si, Ge, C), PRB 39 5566 (1989)
Tersoff88 tersoff88_$(SYS) Si(B) - PRB 37 6991 (1988), Si(C) - PRB 38 9902 (1988) In default, the parameters are set to Si(C). The parameters can be reset to Si(B) by modifying source code, "tersoff88.cpp".
Brenner brenner_$(SYS) C, hydrocarbons

Relation between the parameters in SW potential and in MD++ codes[edit]

The parameters in SW potential model and in MD++ codes are associated, following the rules described in table below. When changing values of the parameters in MD++ codes, make sure you know what you are changing and how.

Parameters in Balamane et al (PRB 46 2250) Parameters in original SW (PRB 31 5262) Variables in MD++
A_1 = ε*A*B*σ^p bb = A_1/aa = B*σ^(p-q)
A_2 = ε*A*σ^q = aa
Z = ε*λ = plam
μ = σ = pss
α = γ pgam = γ*pss
R_c = a*σ = acut
λ_1 = p = rho
λ_2 = q Not Used (0)

"Potential" Problems[edit]

These are some potential files we used in our simulations of molecular structures. Please note that since we use a variety of codes, the potential files will be in a variety of formats. The most common codes used by our group are LAMMPS ( and ParaDyne) and MD++. These codes use different file formats for EAM potentials, so all files should specify which file format. We will also try to provide a reference describing the potential.

Potential Files[edit]

MD++ Files[edit]

EAM Foiles potential for Gold. Ref: Park, H. S., Zimmerman J. A., Modeling inelasticity and failure in gold nanowires. Phys. Rev. B 72, 054106 (2005).

EAM Foiles potential for Copper. Ref: Aubry, S. and Hughes, D. A., Reductions in stacking fault widths in fcc crystals: Semiempirical calculations. Phys. Rev. B 73, 224116 (2006).

LAMMPS SET Files[edit]

EAM Foiles potential for Copper. Ref: Aubry, S. and Hughes, D. A., Reductions in stacking fault widths in fcc crystals: Semiempirical calculations. Phys. Rev. B 73, 224116 (2006).

LAMMPS FUNC Files[edit]