Theoretical studies on electronic properties of a new carbon allotrope with paring of pentagonal and heptagonal rings

Abstract

In recent years, modeling and simulation techniques have been pioneered in the field of prediction existence or ability to synthesize new structures and to study physical and chemical properties. One of these methods is first-principles computations, which are based on the Kohn–Sham density functional theory (DFT). In this work, we predict a new kind of two-dimensional (2D) carbon allotrope by a tiny size building block with interesting properties. A systematic study of the structural and electronic properties on a non-hexagonal flat carbon allotrope has been performed in two different phases that consist of pentagonal (P$\equiv \{C_5\}$) and heptagonal (H$\equiv \{C_7\}$) rings, as well as a carbon nanotube (CNT), by using the DFT computational method. Hence, we obtain optimized lattice structures, bond lengths, density of states (DOS), band structure, the isosurface, and the difference charge density for these both novel two-dimension (2D) materials. The results show that regardless of the type of structure, the nanostructures are electrically metallic. It is anticipated that the results of the present work can be useful in the experimental synthesis of these materials and their potential applications in the future.