Title: Predictive Simulations for Tuning Electronic and Optical Properties of SubPc Derivatives,
Abstract: Boron subphthalocyanine chloride is an electron donor material used in small
molecule organic photovoltaics with an unusually large molecular dipole moment.
Using first-principles calculations, we investigate enhancing the electronic
and optical properties of boron subphthalocyanine chloride, by substituting the
boron and chlorine atoms with other trivalent and halogen atoms in order to
modify the molecular dipole moment. Gas phase molecular structures and
properties are predicted with hybrid functionals. Using positions and
orientations of the known compounds as the starting coordinates for these
molecules, stable crystalline structures are derived following a procedure that
involves perturbation and accurate total energy minimization. Electronic
structure and photonic properties of the predicted crystals are computed using
the GW method and the Bethe-Salpeter equation, respectively. Finally, a simple
transport model is use to demonstrate the importance of molecular dipole
moments on device performance.