Effect of electron and hole doping on the structure of C, Si, and S nanowires

Abstract

We use ab initio density functional calculations to study the effect of electron and hole doping on the equilibrium geometry and electronic structure of C, Si, and S monatomic wires. Independent of doping, all these nanowires are found to be metallic. In absence of doping, C wires are straight, whereas Si and S wires display a zigzag structure. Besides two preferred bond angles of 60°and 120°in Si wires, we find an additional metastable bond angle of 90°in S wires. The equilibrium geometry and electronic structure of these nanowires is shown to change drastically upon electron and hole doping.

Deriving Carbon Atomic Chains from Graphene

“…Interestingly, the formation of a double chain was frequently observed The single carbon atomic chain shown in Fig. 2(f) has a length of about 2.1 nm (corresponds to about 16 carbon atoms) and behaved like an elastic string with a quasilinear arrangement, which is consistent with the theoretical studies [7]. No abrupt junction corresponding to the zigzag-or armchairlike configuration was ever found.…”

“…As one of the most promising candidates, carbonbased nanostructures, either two-dimensional graphene [1] or quasi-one-dimensional carbon nanotubes [2] have opened entirely new perspectives towards the carbon-based electronics. As an ideal covalent one-dimensional (1D) system, a rigid monatomic linear chain of carbon atoms, such as polyyne ( Á Á Á C C À C C Á Á Á ) or cumulene ( Á Á Á C ¼ C ¼ C ¼ C Á Á Á ), has been long expected to function as the component of molecular devices due to its exceptional physical and chemical properties predicted by theoretical studies [3][4][5][6][7]. However, the 1D carbon chain has been little studied experimentally mainly due to the lacking of a reliable and effective way to produce it [8][9][10][11][12][13].…”

Conducting linear chains of sulphur inside carbon nanotubes

“…From this base-centred orthorhombic phase, it is possible to hypothetically extract a one-dimensional (1D) sulphur chain exhibiting a zigzag configuration. This 1D system has been predicted to show a finite electronic density of states near the Fermi level and thus to display metallic behaviour567. Furthermore, Springborg and Jones56 have proposed that the metallic behaviour of sulphur could also result from a free-standing 1D linear configuration.…”

Formation of atomic carbon chains from graphene nanoribbons

“…Useful properties, such as stability, flexibility, charge carriers linear dispersion and high mobility, spin injection with long relaxation times and correlation lengths could lead to applications in spintronics.The possibility to join in the same system the features of one-dimensional wires and the properties of carbon based materials is a very exciting one. The electronic and transport properties of one dimensional carbon systems have already been studied by some groups [5,6,7,8,9,10,11]. However, the lack of reliable and effective ways to produce 1D carbon chains have limited the studies of these systems.…”