Channeling in Gold

The penetration of radioactive 133 Xe and 198 Au ions into oriented monocrystals of gold has been measured in the energy range 20 to 80 keV using an electrochemical sectioning technique. Channeling along low index directions was observed to increase in the order [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], in agreement with theory and with the previous experimentally determined order in other f.c.c. lattices such as copper and aluminium. Two distinct differences in the channeling behavior of ions in gold compared to tungsten are noted: (1) a much smaller fraction of the incident ions remains channeled and (2) the maximum range of the channeled ions is much larger than in tungsten. These differences in behavior are ascribed to the increased multiple scattering due to the higher r.m.s. vibrational amplitude and the lower electronic stopping power in gold. "Supertails" (interstitial diffusion processes) have not been observed. Depth distributions of various other ions at a constant velocity show essentially no dependence on mass.