The electronic gap of bulk NaCl and the band-edge levels of the NaCl(100) surface are calculated using GW methods and self-consistent dielectric dependent hybrid functionals. Optical spectra are calculated by solving the Bethe-Salpeter equations (GW-BSE). For the calculation of the electronic structure of the surface, a procedure based on dielectric dependent range-separated hybrid (sc-DDRSH) functionals is proposed where the $\omega$ parameter is evaluated self-consistently from the surface polarizability tensor. The resulting band-edge energies deviate less than 0.1 eV from the GW results. Both GW and sc-DDRSH results closely match the most recent experimental values of the valence band maximum and the conduction band minimum. The GW-BSE results obtained for the NaCl(100) surface indicate that there are a small number of surface states 0.4–0.5 eV below the first absorption maximum at 7.6–7.7 eV. The calculated optical band gaps of the bulk are 7.7–7.9 eV, close to the range of experimental values.

• Received 21 December 2017
• Revised 19 April 2018

DOI:https://doi.org/10.1103/PhysRevB.97.235447