Electronic stopping power of H and He in Al and LiF from first principles

Non-linearities in the electronic stopping power of light projectiles in bulk Al and LiF are addressed from first principles using time-evolving time-dependent density functional theory. In the case of Al, the agreement of the calculations with experiments for H and He projectiles is fair, but a recently observed transition for He from one value of the electronic friction coefficient to a higher value at v∼0.3a.u. is not reproduced by the calculations. For LiF, better accuracy is obtained as compared with previously published simulations, albeit the threshold remains overestimated.