The molecular dynamics simulations simulated a canonical ensemble using the Nose algorithm with a Nose-frequency of 10 14 Hz at a temperature of 300K. The frequency calculations were computed using a finite differences approach with a displacement width of 0.015 Å to stay within the harmonic approximation. The surfaces were modeled using the slab model with (4x4) unit cells topped by a vacuum region with a height larger than 15 Å. The slab thickness varied between 4 to 6 layers, dependent on the specific surface. The minimum slab thickness was 9 Å.