Simulations can help interpret experiments, as well as predict the band alignment produced by different combinations of semiconductors. The underestimation of band gaps by (semi-)local DFT functionals can lead to errors in the computed band alignment. In principle, the interface band alignment could be calculated using the GW approximation within the framework of many-body perturbation theory. However, owing to the high computational cost, simulations of sufficiently large interface models with enough layers to approach the bulk band gaps are not currently feasible using GW or even hybrid DFT functionals. To circumnavigate this problem, corrections based on the shift of the electrostatic potential can be applied to the bulk band edge positions. The electrostatic potential lineup is relatively insensitive to the method used and converges fast with the number of layers. 108,109 Therefore, the electrostatic potential correction can be calculated using a more computationally efficient method (e.g., semi-local DFT), while the bulk band structure is calculated using a more accurate and expensive method (e.g., GW or hybrid DFT). The electrostatic potential correction may be performed for separate surface slabs of each material or for periodic heterostructures with a relatively small number of layers of each material. 111 Additional corrections may be performed at the semi-local DFT level e.g., to account for the effect of interface strain, 108 and the formation of a dipole in polar interfaces 104,106 Thus, expensive calculations of large interface models are avoided.