Apart from VIRTUAL CHEMIST and CatVS, another virtual platform for catalyst design is QChASM/AARON (Box 3). Contrary to both VIRTUAL CHEMIST and CatVS, QChASM/AARON is an interface to various opensource tools for structural manipulation, TS search and optimization, as well as free energy calculations for %ee determination. While VIRTUAL CHEMIST and CatVS are primarily based on MM, the geometry optimization and energy calculations available through the QChASM/AARON interface are based on QM methods (either SEQM or DFT) accessible through software such as Gaussian, 78 Psi4, or ORCA. QChASM employs a GUI plugin for the Chimera visualizer, which benefits experimental chemists with little to no expertise in command line environments.