Welcome to the organic electronics research group. Our aim is to combine quantum, atomistic, and coarse-graining simulation techniques in an attempt to pred ict macroscopic properties of organic semiconductors.
More detailed description can be found on the
For those who are interested in technical details, an overview can be found here:
Systematic coarse-graining: J. Chem. Theory Comput., 2009, 5, p. 3211
Charge and energy transport: J. Chem. Theory Comput., 2011, 7, p. 3335
Long-range Coulomb interactions: J. Chem. Theory Comput., 2016, 12, p. 4516
Long-range embedding of molecular ions and excitations in a polarizable molecular environment
J. Chem. Theory Comput.
We present a perturbative treatment of localized aperiodic excitations (charge charge transfer and excitonic states) interacting with a periodic molecular environment. The method rigorously accounts for the long-ranged interaction of charges with a net-quadrupolar background with the conditional convergence of the interaction sum removed by bulk or thin-film shape corrections. We illustrate how long-range interactions qualitatively and quantitatively impact the densities of states and level profiles in heterostructures of organic semiconductors investigating the role of molecular architecture packing and orientation. In accounting for mesoscale fields we obtain the energetics of charge carriers in both crystalline and mesoscopically amorphous systems with high accuracy.
Band structure engineering in organic semiconductors
A key breakthrough in modern electronics was the introduction of band structure engineering the design of almost arbitrary electronic potential structures by alloying different semiconductors to continuously tune the band gap and band-edge energies. Implementation of this approach in organic semiconductors has been hindered by strong localization of the electronic states in these materials. We show that the influence of so far largely ignored long-range Coulomb interactions provides a workaround. Photoelectron spectroscopy confirms that the ionization energies of crystalline organic semiconductors can be continuously tuned over a wide range by blending them with their halogenated derivatives. Correspondingly the photovoltaic gap and open-circuit voltage of organic solar cells can be continuously tuned by the blending ratio of these donors.