Electronic structure of three-dimensional graphyne

The roles of π electrons in the electronic structures and optical properties of graphyne

“…The supercell contains two graphyne layers with AB stacking sequence, which has been predicted as the most stable configuration of bulk graphyne [20]. Our calculations show that bulk graphyne has a small band gap of only 0.16 eV.…”

“…In contrast to graphene with identical  bindings, graphyne has three types of  bindings, C(sp 2 )-C(sp 2 ), C(sp)-C(sp 2 ), and C(sp)-C(sp), as shown in Figure 1. A number of theoretical calculations on graphyne monolayer [13,[16][17][18][19] and graphyne-related nanomaterials [20][21][22] have been performed to reveal their unique properties and potential applications. First-principles calculations showed that single-layered graphyne is semiconducting with a small direct band gap of ~0.5 eV at M point [16].…”

Fluorographynes: Stability, structural and electronic properties

“…Electronic properties: our preliminary calculations of GP1 -GP3 demonstrate ( Figure 2, see also [18][19][20]22,26]) that these systems hold very different electronic properties: the network GP1 (called also as 6,6,6-graphyne 19 ) behaves as a semiconductor (with BG ~ 0.54 eV), whereas the band structures of the network GP2 (called also as 14,14,14-graphyne [19]) and the network GP3 (called also as 18,18,18-graphyne [19] or α-graphyne [26]) seem very intriguing: the valence and the conduction bands meet in a single point at the Fermi level, forming the Dirac cones. Accordingly the density of states (DOS) for GP2,3 is zero at the Fermi level and these graphynes behave as a semiconductors with a zero band gap -like graphene [2,6].…”

“…They are considered as possible promising materials for nanoelectronics, for hydrogen storage, as membranes (for example, for hydrogen separation from syngas -as an alternative for nanomeshy graphene), for energy storage applications or as candidates for the anode material in batteries [20][21][22][23][24][25][26]. Thus, the tuning of the properties of these materials should be critical for their further applications.…”

Investigation of the Elastic Properties of Graphenylene Using Molecular Dynamics Simulations

“…Due to these great properties, graphene has found potential applications in several areas such as nanoelectronics, sensors, transistors, batteries, as well as polymer composites [4][5][6] . Caused by these vast potential applications of graphene and carbon nanotubes (CNTs) in addition to various hybridized states of carbon (sp, sp 2 , and sp 3 ), many researchers have devoted their investigations on finding other carbon allotropes which can possess extraordinary physical properties [7][8][9][10][11][12][13] . Graphenylene which was first described by Balaban et al 14 is one of these allotropes that some of the research works have investigated its properties [15][16][17][18][19][20][21][22][23] .The structure of graphenylene (so-called biphenylene carbon (BPC)) has been theoretically predicted [24][25][26] and synthesized 27 .…”