Spin-orbit splittings and energy band gaps calculated with the Heyd-Scuseria-Ernzerhof screened hybrid functional

We assess the Heyd-Scuseria-Ernzerhof (HSE) screened Coulomb hybrid density functional for the calculation of spin-orbit (SO) splittings and energy band gaps. We have employed a set of 23 semiconductors with available experimental data, including group IV elements, and group III-V, II-VI, and IB-VII compounds. The spin-orbit interaction is included in the calculations using relativistic effective core potentials within a second-variation approximation. HSE errrors are similar to those obtained previously without including SO in the calculation and using a weighted average of the SO split bands for the reference value J. Chem. Phys. 123, 174101 (2005). Here we explicitly show that the same good agreement remains after explicitly including SO interaction in the calculations and comparing directly to experimental energy band gaps.