14 Dec 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

Update bundled copy of the Kokkos library to version 3.5.0 (Stan Moore, SNL and the Kokkos developers) PR #3019, PR #3053

Allow GPU package pair styles to be used with newton_pair on (Trung Nguyen, Northwestern) PR #2867

New update to delete_atoms porosity so that atoms can now be selected by region and group (Steve Plimpton, SNL) PR #2984

New pair style sw/mod providing an empirically modified Stillinger-Weber potential suitable for compounds like MoS2 (Jin-Wu Jiang, Shanghai University, Wengen Ouyang, Wuhan University) PR #3041

New pair style nm/cut/split and bond style fene/nm for coarse grain polymer models (Joseph Dietz, Robert Hoy, USF) PR #2958

Support for binary native dump files for read_dump and rerun (Lixin Sun, Harvard) PR #3054, PR #3059


27 Oct 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

New fix acks2/reaxff for ACKS2 charge equilibration and updates to fix qeq/reaxff that add support for fix efield to both charge equilibration methods. (Metin Aktulga, MSU and Stan Moore, SNL) PR #2931

New fix mol/swap for swapping of atom types within a single, randomly selected molecule (Steve Plimpton, SNL) PR #2992

Add support for multi-species potentials to ML-PACE package (Yury Lysogorskiy and the PACE library developers) PR #2968

Preliminary support for OpenMPTarget in KOKKOS package (Rahul Gayatri, NERSC, Chris Knight, ANL, Stan Moore, SNL) PR #2997


29 Sep 2021

This is a stable release.

Details on what has changed in this release (compared to the previous stable release) are here and details for all releases are here.


20 Sep 2021

Details on what is changed by this patch are here and details for all releases are here.

This is release candidate for a new stable version of LAMMPS. If no new changes are needed it will become the stable version.

Only new features or notable changes are highlighted here:

Updates and additions to the programmer guide section of the manual. Specifically, updated guidelines and information for contributing code to LAMMPS (Axel Kohlmeyer, Temple U) PR #2927

Add new command line flag -skiprun to test input files for syntax error as this will skip main loops in run, minimize and similar commands PR #2919


31 Aug 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

Add KOKKOS accelerated styles for shear flow simulations with the nvt/sllod integrator (Emily Kahl, The University of Queensland) PR #2882

New fix ttm/grid with improved file handling and distributed grid. The existing TTM fixes are refactored and modernized. This also generalizes and unbundles the grid communication class from the KSPACE package and thus updates all PPPM and MSM kspace style variants accordingly (Steve Plimpton, SNL) PR #2902

New pair style coul/exclude to remove excluded Coulomb interactions and for use with kspace style scafacos for molecular systems (Axel Kohlmeyer, Temple U) PR #2886

Add functionality to fix property/atom to support per-atom arrays in addition to per-atom vectors (Steve Plimpton SNL) PR #2342, PR #2889, PR #2903

Update the COLVARS package to version 2021-08-06 (Giacomo Fiorin, NIH, and the colvars developers) PR #2863 and PR #2866

Update to fix bond/swap to support a second kind of bond swapping model (Steve Plimpton, SNL) PR #2888


30 Jul 2021

Details on what is changed by this patch are here and details for all releases are here.

This patch release contains a fix for a bug that was introduced in LAMMPS by the 10 February 2021 patch release.

Specifically if your input script references a single element of a global or per-atom array where the first index has more digits than the second index, e.g. c_stress[21][3], then the wrong array element is accessed because the additional digits in the first index were being truncated. In this case the value for c_stress[2][3] would be used. While rare for input script syntax, this bug is serious because the script will silently use the wrong value.

More details are at Issue #2858

We thus encourage anyone using a LAMMPS version from 10 February 2021 to 28 July 2021 inclusive to upgrade to this patch release.


28 Jul 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

Completion of the package reorganization started in the 2 July 2021 release (Axel Kohlmeyer, Temple U) PR #2829

Significant refactor of the REAXFF package and some updates to the QEQ package and corresponding code in the OPENMP and KOKKOS packages to have it better aligned with LAMMPS coding conventions, remove obsolete and dead code and implement missing features like support for compute stress/atom in the OpenMP version of the reaxff pair style. (Axel Kohlmeyer, Temple U, Aidan Thompson, SNL) PR #2708

New pair style tracker command to track properties of pair interactions (Joel Clemmer, SNL) PR #2788

New lammps_gather_bonds() function in the C library interface and corresponding Python module wrappers (Axel Kohlmeyer, Temple U, and Robert Meißner, TU Hamburg) PR #2850

Updates to the CG-DNA package including a new atom style to address issues with tracking contact pairs (Oliver Henrich, Strathclyde U) PR #2827 and PR #2835

Updates to the INTEL package to better support the new LLVM based Intel compilers and transition to use OpenMP pragmas for SIMD (Mike Brown, Intel) PR #2842 and PR #2849

Add support for atom_modify map hash in the KOKKOS package (Stan Moore, SNL) PR #2815

Updates to the C library interface and Python module to support all fix external functionality and make those behave more consistently, also document the calls (Axel Kohlmeyer, Temple U) PR #2837

A new compute heat/flux/virial/tally for the TALLY package to measure virial heat flow from one group of atoms to another (Donatas Surblys, Tohoku U) PR #2841


2 Jul 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

Renamed many packages for clarity, removing the USER designation except for USER-MISC (Axel Kohlmeyer, Temple U) PR #2818

New package DIELECTRIC with boundary element solvers for computing induced charges at interfaces (Trung Nguyen and Monica Olvera del la Cruz, Northwestern) PR #2793

New SO3 descriptor for the MLIAP package (Byungkyun Kang and Qiang Zhu, UNLV) PR #2796

New fabric tensor compute (Joel Clemmer, SNL and Ishan Srivastava, LBL) PR #2795

Variable pH support and bugfixes for Ewald self-energy in fix charge/regulation (Tine Curk, Northwestern) PR #2802


27 May 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

New package USER-HDNNP which provides a new pair style hdnnp, which is an interface to the N2P2 library for Behler-Parinello neural network potentials (Andreas Singraber, U Vienna) PR #2626

New package USER-RANN which provides a new pair style rann and matching potential files for using "rapid atomistic neural network (RANN) potentials (Christopher Barrett and Doyl Dickel, Mississippi State) PR #2570

Update of the bundled Kokkos library to version 3.4.1 (Stan Moore, SNL and the Kokkos developers) PR #2783


14 May 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

New package USER-PACE which provides a new pair style pace computing interactions using the Atomic Cluster Expansion (ACE) (Yury Lysogorskiy and collaborators at ICAMS, Ruhr-Uni Bochum) PR #2699

New Package USER-BROWNIAN for Brownian dynamics time integration of point and extended particles plus updates for fix propel/self (Sam Cameron, U Bristol) PR #2511

New Package USER-MDI to enable client/server mode coupling of LAMMPS with other codes using the MolSSI Driver Interface (MDI) (Taylor Barnes, MolSSI) PR #2611

New fix style "charge/regulation" which implements Monte Carlo sampling of charge regulation (Tine Curk, Northwestern U and Jiaxing Yuan, Shanghai Jiao Tong U) PR #2585

New generalized DPD pair styles: dpd/ext and dpd/ext/tstat (Martin Svoboda, Karel Sindelka, and Martin Lisal, ICPF) PR #2710

Faster and more flexible support for multi style neighbor lists (Joel Clemmer, SNL) PR #2536

New pair style hybrid/scaled that allows combining contributions from different pair styles with constant or variable scaling factors (Axel Kohlmeyer, Temple U) PR #2702

Updated version of pair style bop with bugfixes and performance improvements (Xiaowang Zhou, SNL) PR #2750, PR #2753

GPU package version of pair style lj/smooth (Gurgen Melikyan, HSE University) PR #2706

Update of the bundled Kokkos library to version 3.4.0 (Stan Moore, SNL and the Kokkos developers) PR #2733

Support for atom style spin in the KOKKOS package (Julien Tranchida, Stan Moore, and Svetoslav Nikolov, SNL) PR #2693

New clang-format configuration file in src tree. All files in that tree are prepared so that clang-format can be applied without destroying functionality. (Axel Kohlmeyer, Temple U) PR #2762

Scripts to support building LAMMPS and its documentation on systems without direct internet access (Richard Berger, Temple U) PR #2742


8 Apr 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

New PLUGIN package providing a plugin command that allows loading and unloading of LAMMPS styles from separately compiled shared object files at runtime (Axel Kohlmeyer, Temple U) PR #2650

Refactoring of core LAMMPS code and packages to increase code reuse and readability, simplify text parsing, simplify internal fix/compute generation, improve thread safety (Richard Berger and Axel Kohlmeyer, Temple U) PR #2655, PR #2657, PR #2674, PR #2678, PR #2683, PR #2685, PR #2694, PR #2700

Additional unit test tools and test inputs to increase coverage of automated testing (Richard Berger and Axel Kohlmeyer, Temple U) PR #2308, PR #2653, PR #2658, PR #2679, PR #2681, PR #2682, PR #2695

Improved error/exception detection and handling in the LAMMPS python module (Richard Berger, Temple U) PR #2668


10 Mar 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

Major update of the GPU package with significant performance and compatibility improvements (Mike Brown and Nitin Dhamankar, Intel Corp.) PR #2603, PR #2610, use statically linked OpenCL driver loader with CMake (Axel Kohlmeyer, Temple U) PR #2617, HIP compilation fixes (Richard Berger, Temple U) PR #2622

New pair style lj/relres which allows fine-grained/coarse-grained simulations for lj/cut type interactions (Mark Chaimovich, Russian School of Mathematics, and Aviel Chaimovich, Drexel University) PR #2590

Refactoring of the KIM package commands. Instead of multiple kim_ commands there is now only the kim command which accepts as subcommand. Additional cleanups and improvements to the kim commands (Yaser Afshar, Ryan S. Elliott, Ellad Tadmor UMN) PR #2620, PR #2625, PR #2649

Direct support for neural network (nn) models added to MLIAP package (Pedro Antonio Santos Florez, University of Nevada - Las Vegas) PR #2641

Reader classes for LAMMPS log files and fix ave/chunk output added to the LAMMPS Python module (Richard Berger, Temple U) PR #2631

Unit tester tools for dihedrals and impropers with inputs for most styles (Abhishek Shandilya, RPI and Axel Kohlmeyer, Temple U) PR #2290


10 Feb 2021

Details on what is changed by this patch are here and details for all releases are here.

Only new features or notable changes are highlighted here:

Add support for machine learning potentials using python frameworks to the MLIAP package (Nicholas Lubbers, LANL, and Aidan Thompson, SNL) PR #2508

New 'eam/he' pair style for modeling He bubbles in metals (Xiaowang Zhou, SNL) PR #2556

New Wang-Frenkel pair style ('wf/cut'), a smooth, short range Lennard-Jones like potential (Xipeng Wang and Simón Ramírez-Hinestrosa, Chinese Academy of Sciences, U Cambridge) PR #2435

Refactor processing of embedded citation strings to make them more visible (Axel Kohlmeyer, Temple U and Steve Plimpton, SNL) PR #2545

BACKWARD COMPATIBILITY:

The processing and meaning of the fix_modify energy and fix_modify virial options has been changed. It is now only available for fixes that contribute to the potential energy and the virial. The energy contributions from thermostats and similar fixes can be accessed with the thermo keyword ecouple and the conserved quantity (i.e. etotal + ecouple) is available as econserve. There are corresponding changes to the implementation, so external fixes will have to be adapted or they will no longer compile. All affected fixes in the LAMMPS distribution have been updated.

The LAMMPS python module now contains a version check: When installing the python module, the current LAMMPS version is stored in a __version__ module variable and upon initialization of a LAMMPS instance it is checked against the output from the lammps.version() method which returns the version of the loaded shared library. If they don't match an exception is raised. This helps to detect inconsistent installations of the shared library or module or incorrectly setting LD_LIBRARY_PATH or PYTHONPATH.

Arguments to LAMMPS commands that contain references to compute, fixes, or variables (c_ID, f_ID, v_ID with and without indices) are now more strictly checked for correctness. Inputs that are incorrect but have previously worked by chance will now cause failures. the KOKKOS package option "cuda/aware" has been renamed to "gpu/aware" since Kokkos now also supports AMD GPUs via HIP.

This release has several "invasive" changes to core parts of LAMMPS, so there is an increased risk that something has been broken in a part of the code that is not (yet) covered by our automated tests (which currently cover about 1/3rd of the total code base).