Range parameters of heavy ions in carbon calculated with first-principles potentials

Interatomic potentials for Kr–C, Au–C and Pb–C diatomics have been calculated with Hartree–Fock (HF) and density-functional theory (DFT) methods in order to clarify the origins of discrepancies between available experimental data and the values predicted by Ziegler, Biersack and Littmark (ZBL) theory for range parameters of heavy ions in light targets at energies of about 1–1000 keV. Relativistic effects were taken into account in the evaluations of the potentials. Range parameters have been obtained within the framework of the standard transport theory. Good agreement between the calculated projected ranges and the experimental data in the energy range of 10–1000 keV gives use in the range-projection equations the nuclear energy losses, determined with the first-principles potentials, and the velocity proportional electronic stopping powers by Land and Brennan (LB). Considerable improvement has also been achieved in the description of the projected range stragglings.