Organic semiconductors are promising materials for solar photovoltaic applications because their electronic properties are easily tuned, they are flexible, lightweight and can be solution processed. However, their overall device efficiency is limited in part by exciton diffusion lengths. Increasing both exciton diffusion lengths and constants through the rational design of molecular systems is a priority to increase the overall organic solar cell device efficiency. In recent years, many researchers have investigated the role of packing motif and crystal lattice structure in controlling exciton transport efficiency via phonon assisted transport. Low frequency intermolecular vibrations, or phonons, can both hinder exciton transport via scattering and drive transport by modifying wavefunction overlap, which can alter device efficiency significantly. Indeed, a recent study demonstrated that suppressing electron-phonon coupling by synthetically modifying the side chains of an acceptor molecule resulted in an increase in the device power conversion efficiency from 17.1% to 18.6%. Although a variety of computational studies investigate phonon-exciton coupling in organic semiconductors, it is difficult to directly probe phonon effects experimentally.