LAMMPS is a classical molecular dynamics code, and an acronym for
Large-scale Atomic/Molecular Massively Parallel Simulator.
LAMMPS has potentials for solid-state materials (metals,
semiconductors) and soft matter (biomolecules, polymers) 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
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
(2/14) Added "stable" versions of LAMMPS
to the download page, which undergo more testing than
the incremental versions. Hopefully this makes it easier for users to
upgrade their version only periodically.
(1/14) Added an idea due to John Grime (U
Chicago), to define templates of molecular topology info for systems
with many small molecules, to avoid the memory cost of duplicating the
information. See the atom_style template
command for details.
(1/14) Added MPI-IO support for
reading/writing restart and
dump files in parallel.
(1/14) Added support for 64-bit atom IDs,
so that molecular systems with up to 2^63 = ~9e19 atoms can be
modeled. See Section 2.4 of the
manual for how to enable this option at build time.
(9/13) Released examples/ASPHERE and
examples/KAPPA and examples/VISCOSITY directories. The first has
demonstration scripts for modeling aspherical particles of the various
kinds that LAMMPS allows, including point ellipsoids, rigid bodies,
and line/triangle surface facets for 2d/3d. Animations of the script
outputs have been added to the Movies page. The latter
two have demonstration scripts for computing thermal conductivities
and viscosities, each with 4 different methods.
(8/13) The 3rd LAMMPS workshop was held
in Albuquerque. See the program and PDFs of most of the presentations
at the Workshops link.
(see the Pictures and
Movies pages for more examples of LAMMPS
This is work by Shengfeng Cheng (chengsf at vt.edu) at Virginia Tech
and Gary Grest at Sandia, to model self-assembly of nanoparticles at a
liquid-vapor interface, induced by evaporation of the surrounding
solvent. The quality of the remaining nanoparticle crystal structure
is a result of the competition between evaporation rate and
nanoparticle diffusion time.
The first figure shows snapshots of the simulation from different
views. The second is a Voronoi tesselation of the top layer of the
nanoparticle substrate. The coloring in both figures is based on a
hexagonal order parameter for the local neighborhood of each
particle. The third figure is an animation of the evaporation and
This paper has further details:
Molecular dynamics simulations of evaporation-induced nanoparticle
assembly, S. Cheng and G. S. Grest, J Chem Phys, 138, 064701 (2013).