A "How-To" Tutorial on Using OpenKIM with LAMMPS

The Open Knowledgebase of Interatomic Models (OpenKIM) contains, in part, a suite of curated interatomic potentials that are freely available (at https://openkim.org) for use in interatomic simulations by materials researchers and scientists across the world. OpenKIM "Models" are compliant with the KIM Application Programming Interface (KIM API) and may be used with any Simulator that also supports the KIM API, including LAMMPS, ASE and ASAP, IMD, GULP, DL_POLY, and others. OpenKIM "Simulator Models" are curated interatomic potentials that do not conform to the KIM API and can only be used with specific simulators, such as LAMMPS.

OpenKIM is also a Knowledgebase containing thousands of predictions for important materials properties computed using each of the interatomic potentials (Models and Simulator Models) stored in OpenKIM. These predictions may be browsed and visualized at https://openkim.org. An exciting new feature of OpenKIM is "KIM Input File Queries" which allow a user to embed searches for OpenKIM data directly into their simulator input files. This makes it easy to accomplish tasks like obtaining the equilibrium lattice constant associated with the potential used for a particular simulation.

This brief presentation will provide practical instructions for how a user may obtain OpenKIM Models and Simulator Models (in binary or source code form) on their computing system and use these with their preferred simulator. In particular, the use of OpenKIM Models, Simulator Models, and KIM Input File Queries within LAMMPS will be a focus of the discussion.