abstract
- exciting (Gulans et al., 2014) is a full-potential, all-electron, density-functional theory (DFT) code, which uses linearized augmented plane waves plus local orbitals (LAPWs and LOs, respectively) for valence and semi-core electrons, and explicitly treats core electrons via the Dirac equation. This basis set provides a systematic path for reaching the complete-basis-set limit, relying only on well-controlled numerical approximations. The high precision of the LAPW basis set makes exciting well-suited for the generation of benchmark-quality data, and to serve as a reference for other DFT implementations, especially those relying on pseudopotentials. It has been shown that exciting is able to achieve microhartree precision for total energies in DFT calculations (Gulans et al., 2018). Also in G0W0 calculations, the complete-basis-set limit was attained (Nabok et al., 2016). Its high precision has also been unequivocally demonstrated in the so-called Δ test (Lejaeghere et al., 2016), which compared the relative precision of several DFT codes for a benchmark set of 71 elemental crystals.