This page is a continuous listing of new features and bug fixes for the LAMMPS molecular dynamics package. It also lists periodic "stable" versions which have undergone more testing.
See the unfixed bug page for info on how to report bugs or issues you find wtih LAMMPS.
In some cases, new features change the syntax or operation of an existing input script command, which can cause LAMMPS output to change, or even "break" an earlier working script. These cases are highlighted below with a "BACKWARD COMPATIBILITY" note.
To stay up-to-date with the current LAMMPS, you have two choices:
This page contains a year's worth of new features and bug fixes.
Past years of features/fixes are here: 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004
Periodic summaries of major new features added to LAMMPS are on the history page.
A LAMMPS "version" is the date when it was released, such as 1 Oct 2020. LAMMPS is updated continuously. Each time we fix a bug or add a feature, we make it immediately available in the LAMMPS git repository hosted on GitHub in the "develop" branch. Every 4-6 weeks we publish a feature release, as listed below. Each dated feature release of LAMMPS contains all the new features and bug-fixes in the develop branch up to and including the version date. The version date of the code you are running is printed to the screen and logfile every time you run LAMMPS. It is also on the first page of the HTML version or PDF version of the manual you are reading. It is also in the file src/version.h and in the LAMMPS directory name created when you unpack a tarball.
These are past "stable" versions of LAMMPS, which have successfully passed a suite of build and run tests. This is more testing than is done for the incremental development feature releases listed below.
If you don't want to track the bleeding edge of LAMMPS development, you can download a tarball of the most recent stable version on the download page or from GitHub. A summary of what is in each stable release is provided on the LAMMPS GitHub site.
Earlier stable versions are also available as tarballs on the LAMMPS web site, at this link, using the appropriate date from the list above.
You can use Git to check out a specific stable version in one of two ways, using the tag listed above:
(1) If you do not have an existing checkout:
git clone -b stable_4Nov2016 https://github.com/lammps/lammps.git mylammps
(2) If you already have an existing checkout:
git fetch origin git checkout -b release-4Nov16 stable_4Nov2016
which will create a branch with the name "release-4Nov16", with all the files for that specific stable release.
Likewise, you can use SVN to check out a specific stable version, using the tag listed above:
svn checkout https://github.com/lammps/lammps.git/tags/stable_4Nov2016 mylammps
Additional info on how to track other branches (stable, maintenance, release, develop) of the GitHub LAMMPS repository via Git or SVN are linked to on the download page.
2 Apr 2025
Details on what has changed in this feature release are here and details for all releases are here.
New features or notable changes since the 2 Feb 2025 feature release are highlighted here:
This release has a significant update to error reporting and error messages. Many error messages have now a “pointer” that indicates the offending word causing the error. Also, there is a new page in the documentation: 11.2. Errors and warnings details — LAMMPS documentation with some general advice and specific explanations of certain errors that people often ask about. The corresponding error messages have been augmented to include aURL that will point to the matching paragraphs. (Megan McCarthy, SNL and many core LAMMPS developers) PR #4456, PR #4456
New fix styles for bosonic path integral molecular dynamics (Ofir Blumer, Jacob Higer, Yotam Feldman, and Barak Hirshberg, Tel Aviv University), PR #4479
New elastic-plastic bond style for BPM package (Joel Clemmer, SNL) PR #4462
New region2vmd command for visualizing LAMMPS regions with VMD (Axel Kohlmeyer, Temple U) PR #4468
New compute vacf/chunk command (Axel Kohlmeyer, Temple U) PR #4473
New extxyz dump style for writing extended xyz xyz file (François-Xavier Coudert, CNRS) PR #4519 New fix qeq/rel/reaxff (Navraj S Lalli, Imperial College London) PR #4507
Alternate velocity verlet timestepping option to avoid unphysical sticking in DEM simulations (Dhairya R. Vyas, Northwestern U) PR #4351
Improved molmap option for fix bond/react (Jake Gissinger, Stevens Institute of Technology) PR #4335
New KOKKOS version of dihedral style multi/harmonic (Richard Berger, LANL) PR #4482
Add support to move dipole moments along in rotate and transrot modes of fix move (Gabriel Alkuino, Syracuse U) PR #4490
Add type first option to fix ave/correlate to reduce output and speed up calculation for suitable use cases (Stephen Sanderson, U of Queensland) PR #4493
Add support for using fix adapt with improper styles (Evangelos Voyiatzis, NovaMechanics Ltd.) PR #4467
Change "make fasthtml" to use pandoc instead of sphinx and speed up repeated builds at the expense of them being more approximate (Axel Kohlmeyer, Temple U) PR #4495
BACKWARD COMPATIBILITY:
Using Python 2.x with LAMMPS should now cause an error, also when using Python 3.5 or older
Compiling LAMMPS -DLAMMPS_SMALLSMALL will stop with an error, same for configuring with CMake
When building the LAMMPS manual with "make fasthtml" we no longer use "Sphinx", but "pandoc". This produces an approximate output without many special Sphinx features, but can render most text very quickly and will only update files that were changed, while "make html" using Sphinx will always read and process all files.
4 Feb 2025
Details on what has changed in this feature release are here and details for all releases are here.
New features or notable changes since the 19 Nov 2024 feature release are highlighted here:
New pair style dispersion/d3 to add D3 dispersion correction to DFT based ML potentials (Sonia Salomoni, Sorbonne and Arthur France-Lanord, CNRS) PR #4410
New angle style mwlc for (meltable wormlike chains) (James D. Farrell, Chinese Academy of Sciences) PR #4433
New fix style efield/lepton for more complex electric field calculations with custom expressions (Gabriel Alkuino, Syracuse University) PR #4241
Updates to fix imd to support the IMDv3 protocol and with it connect with MDAnalysis for on-the-fly processing (Lawson Woods, ASU and coworkers) PR #4431
Add MDR contact model to granular pair style (William Zunker and Sachith Dunatunga, MIT; Dan Bolintineanu and Joel Clemmer, SNL) PR #4409
Add capability to use atom style variables to pair style hybrid/scaled (Aidan Thompson, SNL) PR #4435