First-principles study of various hexagonal BN phases

We calculated the electronic and lattice properties of various hexagonal BN (h-BN) phases. They are hexagonal layered structures with different stacking sequences. We discuss the effect of the manner of stacking on the electronic band structures. The lattice properties were optimized automatically by the first-principles molecular dynamics (FPMD) method. Their calculated electronic band structures are nonmetallic and most of their band gaps are indirect. They have flat bands at the valence (conduction) band top (bottom) at some symmetry lines in a Brillouin zone (BZ). The positions of the valence band maximum (VBM) and conduction band minimum (CBM) in their electronic band structures are varied by changing the stacking sequences.