Validation of Computational Models and Codes

Validation and verification are companion processes in assuring the quality and reproducibility of numerical simulations. While verification tends to focus on software, validation is intended to ensure that the model we are simulating accurately reflects the behaviors of the system we are studying. Failure to validate numerical modeling can have catastrophic consequences, as exhibited by the 1998 Mars Climate Orbiter mission, as well as other engineering failures. We discuss the basic principles underlying the validation process, and present examples from our research groups on how the validation process can be applied to molecular simulations.