COMPUTER-SIMULATION OF A SINGLE KINK IN THE [010] SCREW DISLOCATION IN ANTHRACENE-CRYSTALS

The equilibrium configuration for the core of a single kink in the [010] screw dislocation in anthracene crystals has been calculated through computer simulations. The method was based on the assumption of a rigid-body molecule and intermolecular interactions were evaluated using the atom-atom potential method. It followed that a single kink of smooth type was realized in the screw dislocation. The formation energy of the kink was estimated as 0.5 eV. The Peierls stress for the side motion of the kink along the dislocation line, i.e. the Peierls stress of the second kind, was roughly estimated by means of applying an external shear stress. It was much smaller than one twentieth of the Peierls stress of the first kind of the [010] screw dislocation, 2.0 x 10(-1) mu, where mu is the shear modulus.