LAMMPS is a classical molecular dynamics code, and an acronym for
Large-scale Atomic/Molecular Massively Parallel Simulator.
LAMMPS has potentials for soft materials (biomolecules, polymers) and
solid-state materials (metals, semiconductors) and coarse-grained or
mesoscopic systems. It can be used to model atoms or, more
generically, as a parallel particle simulator at the atomic, meso, or
continuum scale.
LAMMPS runs on single processors or in parallel using message-passing
techniques and a spatial-decomposition of the simulation domain. The
code is designed to be easy to modify or extend with new
functionality.
LAMMPS is distributed as an open source code under
the terms of the GPL. The current version can be downloaded
here. Links are also included to older F90/F77
versions. Periodic releases are also available on
SourceForge.
LAMMPS is distributed by Sandia National Laboratories, a US
Department of Energy laboratory. The main authors of LAMMPS are
listed on this page along with contact info and other
contributors. Funding for LAMMPS development has come primarily from
DOE (OASCR, OBER, ASCI, LDRD, Genomes-to-Life) and is acknowledged
here.
(6/12) Added a static and dynamic load
balance via the balance and fix
balance commands, for use with problems where
particles do not fill the simulation box uniformly.
(6/12) Added rerun and
read_dump commands to allow dump files to be
reprocessed by LAMMPS.
(5/12) Added a USER-COLVARS package and
fix colvars command to interface LAMMPS to an
open-source collective variables package for the calculation of
potentials of mean force (PMFs) in various scenarios.
(12/11) Added a run_style
verlet/split command to allow a simulation with
long-range Coulombics (PPPM) to be split across 2 partitions of
processors to boost performance when the FFTs in PPPM become a
bottleneck on large numbers of processors.
(10/11) Added a Fast Lubrication Dynamics
package (FLD, fast form of Stokesian Dynamics), which can be run in
explicit or implicit mode. This is due to contributions from Amit
Kumar and Michael Bybee from Jonathan Higdon's group at UIUC. See
the new pair_style lubricateU command for
more details.
(10/11) Added line segment and triangular
particle types, so that faceted rigid bodies can be modeled in 2d and
3d. See the new pair_style tri/lj command for
more details.
(10/11) Release of the USER-OMP package
which provides OpenMP accelerated versions of nearly all pair styles
and dihedral styles, as well as some fixes, to enable running in
multi-threaded, shared-memory mode on the cores of a multicore
processor. See this section of the
manual for details.
(8/11) Release of the USER-SPH package
which implements smoothed particle hydrodynamics (SPH) in LAMMPS. See
these movies and this user's
guide for more details.
(8/11) Release of the USER-CUDA package
which provides accelerated versions for NVIDIA GPUs of 28 pair styles,
14 fixes, and 4 computes, with the ability to run an input script
entirely on the GPU(s) until a timestep on which CPU calculations are
required. See this section of the
manual for details.
(8/11) Added a USER-MISC package to make
it simpler and quicker to add new single-file features contributed by
users to the main LAMMPS distribution. See this
page for guidelines on how to submit
code for a new feature.
(8/11) Added support for the FFTW3
package as well as KISSFFT (which requires no link to an external FFT
library), when using PPPM for long-range Coulombics.
(see the Pictures and
Movies pages for more examples of LAMMPS
calculations)
This is work by Sergey Zybin (zybin at wag.caltech.edu) and
collaborators at Caltech to model shock-induced instabilities in
explosive materials which have heterogeneous features, such as defects
or interfaces, using the ReaxFF force field.
The figure shows shock loading of PBX in a 3.6M atom model with a
saw-tooth interface between RDX and its polymer binder. The color
represents slip which is highest at the interface.
This paper has further details:
Elucidation of the dynamics for hot-spot initiation at nonuniform
interfaces of highly shocked materials, Qi An, Sergey V. Zybin,
William A. Goddard III, Andres Jaramillo-Botero, Mario Blanco, and
Sheng-Nian Luo, Phys Rev B, 84, 220101 (2011).
(abstract)