Title: Orbital-Free Density-Functional Theory Simulations of Displacement Cascade in Aluminum,
Abstract: Here, we report orbital-free density-functional theory (OF DFT) molecular
dynamics simulations of the displacement cascade in aluminum. The electronic
effect is our main concern. The displacement threshold energies are calculated
using OF DFT and classical molecular dynamics (MD) and the comparison reveals
the role of charge bridge. Compared to MD simulation, the displacement spike
from OF DFT has a lower peak and shorter duration time, which is attributed to
the effect of electronic damping. The charge density profiles clearly display
the existence of depleted zones, vacancy and interstitial clusters. And it is
found that the energy exchanges between ions and electrons are mainly
contributed by the kinetic energies.