Lattice defects in plastic organic crystals. Part 3.—Plastic deformation in pure and impure camphene

Studies of plastic deformation (creep) in camphene single crystals in various stages of purity have revealed that, in common with other plastic crystals, steady-state creep occurs by a dislocation climb process. Variations were observed, however, in the activation energies obtained for the pure and impure specimens. For the pure material the activation energy for creep was approximately 104 kJ mol–1, whereas for the less pure systems it was approximately 51 kJ mol–1. This impurity effect is similar to an effect in succinonitrile.