  Activation of non-basal slip is essential in improving the deformability of
hexagonal crystals. However, the mechanism of non-basal slip remains largely
unknown, especially for complex intermetallics such as Laves phases. In this
work, the prismatic slip systems of C14 Laves crystals and possible metastable
states along the slip paths are assessed using atomistic simulations. Multiple
prismatic stacking fault states with the same lattice pattern but different
site occupancies and chemical distributions are identified at different
inter-atomic layers, temperatures and chemical compositions. The formation of
energetically favorable prismatic stacking faults involves short-range
diffusion which implies the thermally activated nature of prismatic slip. The
outcomes of this work advance the understanding of temperature and
chemical-dependent non-basal slip in Laves phases and can be extended to other
topologically close-packed phases.
