Influence of electrostatic fields on molecular electronic structure: insights for interfacial charge transfer

Molecular and interfacial electronic structure at organic semiconductor interfaces shows a rich and subtle dependence on short- and long-range electrostatic interactions. Interface dipoles can be controlled making use of the anisotropic charge distribution at the interface, often with direct consequences also for the molecular electronic structure. In this Perspective, we will discuss the emerging understanding of how local and collective electrostatic effects control energy level alignment and molecular electronic structure at organic semiconductor interfaces and highlight some of the ramifications for interfacial charge-transfer dynamics. Attention is paid to the validity of the underlying assumptions inherent to the classical electrostatic approach.