MD simulations of GB phase transformations and equilibrium coexistence at 500 K under ambient conditions (a, b), tensile stress (c) and shear stress (d). a, To avoid hysteresis due to the nucleation barrier we start with a two-phase state (a) and monitor the direction of the GB phase junction migration. b, At ambient conditions the pearl phase grows and the junction moves to the left. c, Under tensile stress of 3.95 GPa the domino phase becomes thermodynamically more stable, it grows at the expense of the pearl phase and the junction moves to the right. d, Under a shear stress of 342 MPa parallel to the GB plane in the direction parallel to the tilt axis the domino phase also becomes more stable and grows. The black arrow indicates the initial position of the GB phase junction, while the green line shows the final position. We performed similar simulations at different tensile and shear stresses and conclude that in the model the equilibrium coexistence between the pearl and domino phases at this temperature of 500 K can be achieved at around 3.3 GPa tension or within the range 200–350 MPa for shear stress. The simulations of equilibrium coexistence confirm that pearl and domino are examples of GB phases. The MD simulations ran for 200 ns to 400 ns.