In this computational study we have examined the ability of generic crystalline substrates to promote ice nucleation as a function of the hydrophobicity and the morphology of the surface. It turns out that the lattice mismatch of the surface with respect to ice, customarily regarded as the most important requirement for a good ice nucleating agent, is at most desirable but not a requirement. Furthermore, we find a complex interplay between morphology and hydrophobicity that can lead to the formation of up to three different faces of ice on the same substrate.
