Original Workflow for SMART Descriptor Calculation. The workflow for generating SMART descriptors has been partially disclosed by Davies and Sigman. In this workflow, molecular probes were added to catalysts, checked for atomic overlap with the structure, then conformer searched, all requiring manual user input for every step. This implementation was time consuming and limited the possibility for high throughput catalyst parametrization. The most significant limitation of the original workflow is that probe conformer ensembles were generated using the OPLS3e forcefield and a torsional Monte Carlo (MC) algorithm implemented in MacroModel, a commercial software distributed by Schrödinger. Molecular descriptors were then calculated using the free program UCSF Chimera . SMARTpy employs exclusively free and open-source Python modules to generate conformer ensembles. Additionally, the package employs multiple methods for computing an array of steric descriptors.