To perform the DFT calculations on bilayers the optimal stacking configuration for the bilayer must be found. There are two categories of stacked bilayers: those where the simulation cell is constructed from the unit cells of the two monolayers; and those where the cell needs to be constructed from a larger supercell of each monolayer. For the former, we obtain the stacking equilibria by performing a geometry relaxation for three stacking configurations AA, AB and AB'. These configurations are displayed in Figure . The structure with lowest energy is then taken as the equilibrium stacking configuration. For the incommensurate unit cells such as the boron nitride|silicon carbide bilayer (formed from 5 × 5 boron nitride unit cells and 4 × 4 silicon carbide unit cells), sliding one monolayer over the other in such large bilayers does not significantly affect the binding energy. Hence, we do not search for equilibrium stacking configurations in these bilayers.