Eric Welch @Eric-Welch

I am trying to calculate band offsets for two materials (CsPbBr3 and CuI) and I am comparing equal increases in layer thickness. In this paper (Article Halide Perovskite Heteroepitaxy: Bond Formation and Carrier ...

) they include core electron energy differences between the bulk and the surface slab models in their offset calculations (Pb 1s energy level). In VASP, is this as simple as switching on ICORELEVEL = 1 and then comparing the core energy level of interest that has been printed to the OUTCAR??

Also, when ICORELEVEL = 1 is added to the incar, the core Pb 1s eigenvalue reported to the OUTCAR for a system comparing GGA = PS vs HSE06 for bulk CsPbBr3 is -88055.110 eV and 86.216 eV repectively for the two exchange correlation methods. Why are these values off by 3 orders of magnitude??

When calculating band offsets based on the method from the above paper, are the KS eigenvalue band edges simply those eigenvalues output to the EIGENVAL/DOSCAR file (plus or minus the Fermi energy)??