Additionally, the final coordinates of our Drude PET model material were used to further study the electronic and structural properties of an amorphous PET slab in vacuum and water. To create our slab model in vacuum, we increased the z-axis dimensions of the simulation box by 20 Å on both sides, while keeping the x-and y-axis box dimensions constant to preserve interactions across the periodic boundaries. To build the solvated system, we converted the system to its additive counterpart by deleting the Drude oscillators and lone pairs and solvated the enlarged box with CHARMM-modified TIP3P water to fill the open volume. The energy of the additive system was minimized, followed by equilibration for 500 ps using the protocol described above. The solvated, additive system was converted to Drude following the protocol described below. Equilibration was carried for both in vacuo and solvated Drude systems for 500 ps using the semiisotropic Monte Carlo Membrane barostat mentioned above. For the in vacuo system, the Monte Carlo Membrane barostat with a fixed z-axis was used to impose a vacuum layer. Production runs for each system were carried for 100 ns and coordinates were saved every 10 ps.