Abstract
Single crystals of GaSb were irradiated with 2MeV electrons in an ultrahigh-voltage electron microscope. Electron irradiation at low temperatures first induces chemical disordering and, with increasing total electron dose, topological disordering takes place. Chemical disordering and topological disordering become more difficult with increasing irradiation temperature and is completely suppressed at temperatures above 300K. Upon annealing, the topologically disordered phase formed at low temperatures becomes unstable at 300K and changes into the chemically disordered phase, while the chemically disordered phase changes into the ordered phase.