“…From our calculations, the ratio of the surface energies per unit area ␥ hkl /␥ 100 are 1.0, 0.97, 0.93, and 0.87 for the ͑100͒, ͑111͒, ͑211͒, and ͑110͒ surfaces, respectively, compared with the values 1.0, 0.87, 0.80, and 0.71 obtained from a bond-cutting model. 34 We see that even the simplest bond-cutting models predict correctly the trend of the surface energies. When we compare the numbers, we see that the bond-cutting model overestimates the surface energies of less compact orientations relative to the most compact ͑110͒ orientation.…”