Organic photovoltaics (OPVs) utilize strongly absorbing blends of pi-conjugated organic molecules to convert light into electrical power.  Efficient OPVs consist of two different molecules or polymers- one of which functions as an electron donating compound while the other acts as an electron accepting compound.  Charge transfer and separation take place at a molecular interface between these electron donating and accepting compounds, thus the nature of this interface plays a critical role in the photovoltaic performance of the device.  Using multiple analytical tools, including measurements of the charge-transfer state energy, combined with specifically designed polymers, we explore how molecular details at this interface impact the performance of OPVs.  In addition to the completed research presented here, I’ll also highlight the photoelectron spectroscopy, inverse photoelectron spectroscopy, device characterization, and research directions that my group will be working on here at UK.