Surface energies of AlN allotropes from first principles
نویسندگان
چکیده
In this letter we present first-principles calculations of the surface energies of rock-salt (B1), zinc-blende (B3) and wurtzite (B4) AlN allotropes. Of several low-index facets, the highest energies are obtained for monoatomic surfaces (i.e. of only either Al or N atoms): [Formula: see text] and [Formula: see text]. The difference between Al- and N-terminated surfaces in these cases is less then 20 meV/Å2. The stoichiometric facets have energies lower by 100 meV/Å2 or more. The obtained trends could be rationalized by a simple nearest-neighbour broken-bond model.
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