Electrocatalysts provide an interesting challenge to beyond-DFT methodologies because they are composed of catalysts that can be metallic , semimetallic , or semiconducting , and they are in contact with molecules. As such, they require beyond-DFT exchange-correlation effects and a treatment of partially occupied electronic orbitals for their accurate description. Additionally, realistic models of electrocatalytic systems require significantly larger computational models , both in terms of atoms in the simulation cell and the total volume of the simulation cell, and this increases the cost of such calculations relative to simpler bulks solids or molecules by at least an order of magnitude. This increased cost requires highly efficient and parallel software that can run on modern, GPU-based supercomputers .