ABSTRACT
This chapter devotes to the progress achieved in the theoretical understanding of how the chemical nature and molecular architecture of p-conjugated chromophores determine: the intermolecular noncovalent interactions that impact the molecular packing arrangements in thin films or crystals; and polarization phenomena in the solid state, both of which govern the material electronic and optical properties. It present a brief overview of recent advances in the density functional theory (DFT) description of organic electronic systems, as well as a discussion of the most pressing challenges and of important caveats. Ground-state DFT calculations can be used to calculate a number of important parameters, including molecular geometries, vibrational frequencies, electronic band-structures, electronic densities, and density differences, or dipole moments. DFT-based methodologies have been widely applied to characterize the geometric and electronic structures of various metal and conducting oxide surfaces and their interfaces with organic molecular layers of relevance to opto-electronic device applications.
