Optical response and band structure of LiCoO2 including electron-hole interaction effects (vol 104, 115120, 2021)

The calculation of optical properties of LiCoO2 presented in Phys. Rev. B 104, 115120 (2021) are revisited with improved accuracy calculations. An error in the polarization dependence in the previous work is pointed out and corrected here. The exciton binding energies are found to be somewhat smaller than previously reported- about 0.9 eV rather than 2 eV. The spatial extent of the excitons is analyzed here and shows interesting differences between dark and bright excitons. The effects of the local field effects are also clarified and found to be largest in the direction perpendicular to the layers.