LAMMPS Users ManualLarge-scale Atomic/Molecular Massively Parallel Simulator

http://lammps.sandia.gov - Sandia National LaboratoriesCopyright (2003) Sandia Corporation. This software and manual is distributed under the GNU General Public License.

Table of ContentsLAMMPS Documentation.............................................................................................................................1

Version info:............................................................................................................................................11. Introduction.........................................................................................................................................4

1.1 What is LAMMPS......................................................................................................................41.2 LAMMPS features......................................................................................................................5General features................................................................................................................................5Particle and model types...................................................................................................................5Force fields........................................................................................................................................5Atom creation....................................................................................................................................6Ensembles, constraints, and boundary conditions............................................................................6Integrators.........................................................................................................................................7Diagnostics........................................................................................................................................7Output...............................................................................................................................................7Multi-replica models.........................................................................................................................7Pre- and post-processing...................................................................................................................7Specialized features..........................................................................................................................71.3 LAMMPS non-features...............................................................................................................81.4 Open source distribution.............................................................................................................91.5 Acknowledgments and citations...............................................................................................10

2. Getting Started...................................................................................................................................122.1 What's in the LAMMPS distribution........................................................................................122.2 Making LAMMPS....................................................................................................................132.3 Making LAMMPS with optional packages..............................................................................192.4 Building LAMMPS as a library................................................................................................212.5 Running LAMMPS...................................................................................................................222.6 Command-line options..............................................................................................................232.7 LAMMPS screen output...........................................................................................................272.8 Tips for users of previous LAMMPS versions.........................................................................28

3. Commands.........................................................................................................................................303.1 LAMMPS input script...............................................................................................................303.2 Parsing rules..............................................................................................................................313.3 Input script structure.................................................................................................................313.4 Commands listed by category...................................................................................................333.5 Individual commands................................................................................................................33Fix styles.........................................................................................................................................34Compute styles................................................................................................................................35Pair_style potentials........................................................................................................................35Bond_style potentials......................................................................................................................37Angle_style potentials.....................................................................................................................37Dihedral_style potentials................................................................................................................37Improper_style potentials................................................................................................................38Kspace solvers................................................................................................................................38

4. Packages............................................................................................................................................394.1 Standard packages.....................................................................................................................394.2 User packages...........................................................................................................................40USER-MISC package.....................................................................................................................41USER-ATC package.......................................................................................................................41USER-AWPMD package................................................................................................................41

LAMMPS Users Manual

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Table of ContentsUSER-CG-CMM package..............................................................................................................42USER-CUDA package....................................................................................................................42USER-EFF package........................................................................................................................43USER-EWALDN package..............................................................................................................43USER-OMP package......................................................................................................................44USER-REAXC package.................................................................................................................44USER-SPH package........................................................................................................................44

5. Accelerating LAMMPS performance................................................................................................465.1 OPT package.............................................................................................................................475.2 USER-OMP package................................................................................................................475.3 GPU package............................................................................................................................495.4 USER-CUDA package..............................................................................................................515.5 Comparison of GPU and USER-CUDA packages...................................................................53

6. How-to discussions............................................................................................................................566.1 Restarting a simulation.............................................................................................................566.2 2d simulations...........................................................................................................................586.3 CHARMM, AMBER, and DREIDING force fields.................................................................586.4 Running multiple simulations from one input script................................................................596.5 Multi-replica simulations..........................................................................................................616.6 Granular models........................................................................................................................616.7 TIP3P water model...................................................................................................................626.8 TIP4P water model......................................