As with the amorphous PET slab, we also examined the electronic polarization behavior of PET chains in the crystal film as a function of their exposure to the solvent. As shown in Figure , the total dipole moments of PET residues in the additive system were insensitive to the their position in the crystal film, producing an average dipole moment of ∼0.5 D in all layers. Meanwhile, in the Drude system, the total dipole moments were increased among the residues at the crystal surfaces, with layers ±3 manifesting a total dipole moment of ∼1 D. As shown in Figure , the increased induced dipole moment of the PET residues at the crystal-water interface (i.e., layers ±3) arises from the water exposure and this effect is confined to the layer in direct contact with the solvent. Moreover, the small induced dipoles observed for the PET residues in the crystal film in vacuum suggest the inner layers of the PET film produce a very small, localized electronic polarization response on the interfacial layers.