The Interatomic Potentials Repository (IPR) at the National Institute of Standards and Technology (NIST) provides a valuable service to the molecular simulation community. The NIST IPR accepts interatomic potential parameter files contributed by developers and provides access to these files and accompanying information on their website. Links are also provided to results obtained using these potentials from computations performed by NIST IPR staff.
The OpenKIM project collaborates with NIST by regularly exchanging information. Many of the interatomic models archived in OpenKIM were originally submitted to the NIST IPR (in such cases, a link to the original NIST content is provided on the model's page on openkim.org). It is the intention of the OpenKIM project to continue working closely with the NIST IPR to serve the needs of the materials research community.
Despite the similarities, OpenKIM is fundamentally different from the NIST IPR. OpenKIM not only stores parameter files and completed calculations, but is also a computational infrastructure that is integrated with major simulation codes that support the KIM Application Programming Interface (API) standard. Potentials in OpenKIM are curated subject to full provenance control (including versioning to ensure reproducibility of results) and can be used seamlessly with KIM-compliant codes. In addition, archived potentials are verified for coding correctness and tested for their predictions within the OpenKIM system using an automated framework called the KIM Processing Pipeline. Results of these calculations are accessible programtically via a web query interface. OpenKIM is a member of DataCite and issues all content in openkim.org DOIs that can be cited in publications. See the Features of the OpenKIM System for more details on OpenKIM capabilities that differ from the NIST IPR.