Electronic and elastic properties of two-dimensional carbon planes

Motivated by the recent discovery of the experimental possibility to obtain two-dimensional (2D) crystals and the permanent interest in carbon materials, we perform a theoretical investigation of the stability and electronic properties of 2D graphite (graphene) and also of some new similar carbonic structures. Using the ABINIT program we have found that the planes composed from the expanded radialenes possess metallic properties, similar to those reported recently for the nanotubes based on similar carbonic structures. Furthermore, the evaluation of the Young's modulus has shown that the expanded radialenes-based planes may have different elastic properties, in particular they may be stiffer than graphene.