Interaction energies at twin boundaries and effects of the dihedral reentrant and salient angles on the growth morphology of twinned crystals

Twin-boundary energies are calculated with the Lennard-Jones 6-12 potential function for the (110) and (310)-twin laws of orthorhombic even n-alkane crystals. In agreement with experiment, the calculations show that the higher the interaction energy along the twin boundary, the higher the probability of observing the corresponding twin. According to the values of the reentrant angles, the adsorption sites near the twin boundary may act as permanent growth sites (kinks) where growth takes place spontaneously and leads to a crystal elongated in the direction of the twin boundary.