Theoretical prediction of a new two-dimensional carbon allotrope and NDR behaviour of its one-dimensional derivatives
By using state of the art theoretical methods we have predicted a new two-dimensional (2-D) carbon allotrope. This new planar carbon framework is made of hexagons, octagons and pentagons and hence named as HOP graphene (HOPG). The possibility of existence of HOPG is evident from its dynamical stability as confirmed by phonon-mode analysis and also from an energetic point of view since it is energetically more favorable than recently synthesized graphdiyne. The band structure shows the metallic behaviour of this new form of carbon allotrope. We also explored the electronic structure and transport properties of a 1-D derivative (nanoribbon) of HOPG. Most of the nanoribbons exhibit multiple negative differential resistance (NDR) behaviour with high peak to valley ratio.