Dynamic variables were introduced into Parrinello-Rahman simulations which permitted slipping of the simulation cell, relative to its periodic images above and below a specified plane. Equations of motion were derived which showed that slip was governed by a dynamic balance between an internal virial traction and an external glide force. The phenomenology of martensitic transformations (habit plane, macroscopic deformation corresponding to an invariant plane shear) was introduced by imposing Lagrangian constraints on the dynamics of the cell and slip variables. A model structural transformation was simulated, with and without slip, and with rational and irrational habit planes. The permitting of slip on an irrational habit plane markedly lowered the barrier to transformation. The results modelled edge and screw dislocations, slip, cross-slip, dissociation and twinning. A glissile dislocation interface was also observed.

Atomistic Simulations with Slip Boundary Conditions. J.V.Lill, J.Q.Broughton: Physical Review B, 2001, 63[14], 144102 (17pp)