Reflection of Atoms by a Crystal

Abstract

Directional distribution of cadmium, mercury, sodium, and hydrogen atoms reflected from rock-salt.—Beams of cadmium and mercury atoms striking a clean rock-salt surface are reflected so that incident and reflected beams make equal angles with the normal to the crystal surface. The divergence of the reflected beam is only a little greater than that of the incident beam. Sodium is not reflected from a rock-salt surface. Hydrogen atoms striking a rock-salt surface leave as atomic hydrogen. The distribution of the directions in which they leave the surface has never been the same for any two crystals. This may be due to failure to remove all adsorbed gas.