LAUSR

Abstract The modified Becke-Johnson exchange potential proposed by Tran and Blaha (TB-mBJ) is useful for accurate calculations of electronic band structures of solids. In this view, we used such potential together with spin–orbit coupling to calculate the electronic and optical correlation effects in bulk gold (Au) via first principle DFT. Inclusion of the relativistic effects in the simulation were found to play vital role on the optical properties of bulk Au. Furthermore, the imaginary part of the dielectric function of Au disclosed good agreement with the experimental results. Disclosure of good agreement between simulation and experimental results (up to Fermi level) was due to the improvement in the band structure of bulk Au achieved by incorporating spin–orbit coupling.