XtalOpt is a free and truly open source evolutionary algorithm designed to predict crystal structures. It is implemented as an extension to the Avogadro molecular editor.
XtalOpt runs on a workstation and communicates with a PBS server via ssh to perform calculations using GULP, VASP, pwSCF
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(Quantum ESPRESSO), or CASTEP. There is no special set up needed server-side, just install XtalOpt on the workstation and it's ready to go! [Less]