Graphitic nanofilms as precursors to wurtzite films: theory.
Periodic ab initio density functional calculations on ultrathin films of AlN, BeO, GaN, SiC, ZnO, and ZnS demonstrate the stabilization of thicker films terminating with the polar {0001} surface via charge transfer and metallization of the surface layers. In contrast thinner films remove the dipole by adopting a graphiticlike structure in which the atoms are threefold coordinate. This structure is thermodynamically the most favorable for these thinner films. Implications for the crystal growth of wurtzite materials are discussed.
Freeman
Colin L
CL
School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
Claeyssens
Frederik
F
Allan
Neil L
NL
Harding
John H
JH