Fig. 1: Electronic excitation energy for 1 keV silicon projectiles along the 〈001〉 channel in Si, obtained with different pseudopotentials.

The resulting electronic stopping values, represented by the slope of these curves, vary by about 1%, except for the OPIUM potential³⁰, which deviates by only 6%. This is particularly noteworthy as the OPIUM potential was purposefully built with a large convergence error. A small vertical offset between the energy curves at the origin has been added for visualization purposes. The inset shows the percentage deviation between the electronic stopping power predicted by the ONCV PBE³⁴ and HSCV LDA³¹ potentials for a range of projectile energies. The deviations are less than 3%.