We now turn to detailed benchmarking of our model systems against experimental crystal structures and spectroscopic data to confirm our choice of the lowest-energy D-A dimer as a sufficient model for these crystalline materials. As briefly described in 3.1, we performed scans of the S0 PES of the Npe:TCNB molecular cluster (MC) and identified six structures as candidate dimer models of the extended co-crystals, shown in Figure . A previous study identified two low-energy minimum geometries of the Npe:TCNB dimer. In the six conformers identified here, two agree with the previously reported geometries by Zhu et al., including the lowest-energy isomer, a. We find that multiple minima exist upon rotation of TCNB with respect to the naphthalene of Npe, resulting in our identification of two low-energy structures that differ by 0.009 eV (b) and 0.062 eV (c) from the lowest-energy structure. We also identify a structure at 0.107 eV for which TCNB is localized to the pyridine of the Npe (d). The highest energy structure (0.179 eV, f) found in this study is structurally similar to the higher energy structure determined by Zhu et al., differing only by a slight rotation of the naphthalene ring. Finally, a folded structure was located at a relative energy of 0.111 eV (e). In this structure, the Npe molecule is folded in a V-shape and TNCB is positioned on top of the naphthalene moiety.