From Zero to Infinity: Customized Atomistic Calculations for Crystalline Solids —Applications to Graphene and Diamond

<strong>We demonstrate that a suitable atomistic method with judicially selected nanoclusters/ nanocrystals (in real space) supplemented with general symmetry and dimensionality arguments, can give surprisingly good results for macroscopic properties of the infinite crystalline solid, such as bandgaps, cohesive energies, as well as aromaticity (if any), at minimal computational cost and maximum physical insight. For graphene on top of these properties the present approach can successfully describe in real space and illuminate many of its exotic properties, which are usually introduced in k-space, such as Dirac points or topological insulators. An early version of this methodology has been very successfully applied and extrapolated to Si, Be, BeH, CdSe, MgH, crystals and nanocrystals, with almost chemical accuracy in most cases. Here, after a pedagogical and critical review of the earlier results, we introduce a new combined and expanded approach to comparatively describe the electronic