The influence of exact exchange corrections in van der Waals layered narrow bandgap blackphosphorus

Abstract

We study the electronic structure of black phosphorus by combining state-of-the-art densityfunctional theory, multiple scattering calculations and electron energy loss spectroscopy.The hybrid functionals HSE03 and PBE0 are tested to investigate whether they give animproved description compared to the more traditional PZ-LDA and PBE-GGAfunctionals. These calculations are compared with investigations of the conduction bandusing electron energy loss spectroscopy and calculations based on the real-space multiplescattering approach, and previous determinations of the bandgap. The hybrid functionalHSE03 gives an improved correspondence with these experiments. Comparisons of thecalculated valence band with previous XPS studies yield acceptable agreement for thetraditional functionals, while the results from the hybrid functionals are less satisfactory,since the hybrid functionals overestimate the valence band width significantly.