LAMMPS website

Latest Features and Bug Fixes in LAMMPS

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: 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.

What version of LAMMPS do you have?

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.

Stable versions

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 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 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.

8 Feb 2023

Details on what changed in this feature release are here and details for all past releases are here.

Only new features or notable changes are highlighted here:

Port of the AMOEBA package code to the GPU package (Trung Nguyen, U Chicago) PR #3599

Port of pace/extrapolation pair style to KOKKOS (Yury Lysogorskiy (ICAMS, RUB) PR #3585, PR #3629

Port of pair styles lj/expand/coul/long and lj/cut/dipole/cut and atom style dipole to KOKKOS (Trung Nguyen, U Chicago) PR #3623

Port of the ML-IAP Python interface for PyTorch to KOKKOS (Matt Bettencourt, NVIDIA) PR #3577, PR #3606

New pair style meam/ms implementing the multi-state MEAM extension including port to KOKKOS (Drew Rohskopf and Aidan Thompson, SNL, and Mike Baskes, LANL, UNT) PR #3608

Remove mesont/tpm pair style and related styles as well as the corresponding Fortran library from MESONT package as they are superseded by the mesocnt pair and bond/angle styles. (Axel Kohlmeyer, Temple U) PR #3605

New LEPTON package that allows custom potential functions through evaluating expressions provided as string through the Lepton library written originally for OpenMM (Axel Kohlmeyer, Temple U) PR #3571, PR #3590

New angle_write and dihedral_write commands (Axel Kohlmeyer, Temple U) PR #3573

New compute efield/wolf/atom command that can approximate the electrostatic field at atom positions using Wolf summation (Axel Kohlmeyer, Temple U) PR #3551

Bugfix for DPD-BASIC pair styles and their accelerated versions when used with bonds and special_bonds factors that are not 0 or 1. (Axel Kohlmeyer, Temple U) PR #3575

Updates to the DIELECTRIC package that reverses the logic of how to store original and scaled charges and thus results in more consistent behavior of computes and fixes outside the DIELECTRIC package (Trung Nguyen, UChicago) PR #3576

Support for ABC-FIRE variant of FIRE minimizer (Sebastian Echeverri Restrepo, King's College London) PR #3591, PR #3594

Support for "equal" mode of NEB (Tom D Swinburne, CNRS), PR #3596