Lucas Visscher: Combining electronic structure methods with subsystem DFT: Theory and Applications

Due to advances in computer technology and algorithms the standard molecular-orbital based methods of quantum chemistry (DFT, CC) can nowadays be applied to complex biological systems or sophisticated models of molecules on a surface by simply treating the whole system as one giant supermolecule. While this brute-force approach can be computationally feasible, interpretation of results of the calculations in terms of chemically meaningful concepts requires a posteriori analysis to reconstruct the concept of molecules and functional groups from the supermolecular wave function.

An attractive alternative is to utilize chemical knowledge from the outset and treat complex systems as a set of well-defined interacting subsystems. In this talk I will discuss our experiences[1] with subsystem density functional theory[2], which provides a natural connection to qualitative chemical models. I will discuss in particular the merits of this approach in the combination of different electronic structure methods[3] in an overall response framework for the calculation of molecular properties[4].