CP2K
Atomistic simulation package combining Gaussian and plane-wave representations, with DFT, molecular dynamics, classical force fields and multiscale modeling.
Where it fits
Condensed-phase chemistry, liquids, interfaces and ab initio molecular dynamics.
Limits and practical considerations
Basis sets, auxiliary grids and sampling must all be converged for the target observable.
Licensing and access
Freely available under the GPL; the project does not promise warranty or direct support.