First principles quantum calculations for graphyne for electronic devices.

Moving beyond traditional 2D materials is now desirable in order to have switching capabilities (e.g., transistors). Here we propose using γ graphyne-n because, as shown in this paper, obtaining regions of the electronic band structure which act as valence and conduction bands, with an apparent bandgap, are found. Electron spatial density and electronic band structures with ε(k) vs. k are calculated for graphyne-1 and graphyne-2 having respectively, one and two triple C-C carbon-carbon bonds between adjoining benzene rings; such side by side comparisons never before done. The ab initio quantum calculations were performed using both the local density approximation (LDA) and the generalized gradient approximation (GGA) for density functional theory (DFT).