First-principles approaches provide a wealth of insight into properties and processes in materials and chemistry. From a computational point of view, the ongoing challenges are: (i) Real materials can be complex even if they are conceptually simple, and (ii) the underlying theory must be reliable and feasible for the task at hand. This talk summarizes the vision and concepts behind the FHI-aims all-electron electronic structure code, a long-term development to address both challenges that is led by our group. Specific efforts include scalability towards large systems and on large massively parallel computer platforms, as well as an ongoing thrust towards many-body approaches in addition to standard density-functional theory approaches. Ongoing work in our group includes graphene on SiC as an exceptionally high-quality platform to study interfacial phenomena between carbon-based and other functional materials. Large-scale, essentially strain-free simulations reveal why large-scale, high-quality monolayer graphene films can be grown directly on the Si-face , but not on the C-face of SiC, and how manipulation of the films by H intercalation leads to films with properties approaching those of free-standing graphene on this substrate .
 L. Nemec, V. Blum, P. Rinke and M. Scheffler, Thermodynamic Equilibrium Conditions of Graphene Films on SiC, Physical Review Letters 111, 065502 (2013).
 J. Sforzini, L. Nemec, T. Denig, B. Stadtmüller, T.-L. Lee, C. Kumpf, S. Soubatch, U. Starke, P. Rinke, V. Blum, F.C. Bocquet and F.S. Tautz, Approaching truly freestanding graphene: The structure of hydrogen-intercalated graphene on 6H-SiC(0001), Physical Review Letters, accepted for publication (2015).