Fig. 3
From: Precision and efficiency in solid-state pseudopotential calculations
Band structure of FCC Pb along a high-symmetry path, for several pseudopotential libraries (top panel). The valence bands are almost identical to each other, while some differences appear in the conduction bands: the SG15 bands deviate from the other bands around 7–10 eV over the Fermi level and a flat ghost state in the GBRV bands is clearly visible at around 8 eV. These differences between band structures can be compressed into the bands distances ηv and η10, reported in units of meV (bottom panel). In addition, ghost states in the band interval considered can be automatically detected as peaks in the η function, hence simplifying greatly the verification of spectral properties
