J. Guerrero-Sánchez

Ab-initio study of ReCN in the bulk and as a new two dimensional material

First principles total energy calculations have been applied to describe the ReCN bulk structure and the formation of ReCN monolayers and bilayers. Results demonstrate a strong structural rearrangement in the monolayer due to a reduced dimension effect: an increase in the lattice parameter, accompanied with the contraction of the distance between the C and N planes. On the other hand, a ReCN bilayer has structural parameters similar to those of the bulk. Surface formation energies show that the monolayer is more stable than bilayer geometries. Although bulk ReCN shows a semiconductor behavior, the monolayer ReCN presents a metallic behavior. This metallic character of the ReCN monolayer is mainly due to the d-orbitals of Re atoms.

Nitrogen induced phosphorene formation on the boron phosphide (111) surface: a density functional theory study

Nitrogen induced phosphorene formation on top of the BP (111) surface is investigated using periodic density functional theory (DFT) calculations. We have considered adsorption/incorporation of different amounts of N, from 1/4 to 1 monolayer. Results demonstrate that the incorporation of a full N monolayer into the second P monolayer drives the formation of a P atomic wire at the surface. Adsorption of two monolayers on top of the phosphorus atomic wire results in the formation of a phosphorene atomic structure. Surface formation energy calculations indicate that for most of the allowed chemical potential range, the structure with the P zigzag atomic wire array is stable. However, for phosphorus rich conditions, the formation of a phosphorene configuration is also possible with almost the same formation energy. The phosphorene structure is bonded by van der Waals forces to the P atomic wire resembling the bilayer–bilayer distance in black phosphorus. From these results, it is clear that the N incorporation plays a key role in the stability and formation of phosphorene.