X-ray photoelectron spectroscopy(XPS) has been used to follow oxide film gr
owth on pure Nd surface over a wide range of exposure to oxygen and air. Ox
ide film was noticed to consist of oxide, hydroxide and chemically absorbed
water, all of which exhibited logarithmic-type growth kinetics. The oxide
and chemically absorbed water stop growing after a certain exposure, wherea
s the hydroxide,which plays a significant role ultimately, shows continued
and persistent growth.