To discuss the molecular orientation of 4MPy and 4ABA, it is helpful to frame the matter of molecular orientation using Raman selection rules that have been developed for SERS. SERS intensity for a given Raman mode depends on the symmetry of its tensor with respect to the surface for a fixed orientation of a molecule on a plasmonic surface. However, obtaining knowledge of the Raman tensors of different modes is difficult, and the tensors can change on adsorption, as in the case of chemisorption. Moreover, it is difficult to describe local field polarization at the molecule and how that polarization connects with the Raman enhancement factor. Some advances have been made regarding these problems, especially for the case of a flat metal surface and the research on the (flat) plasmonic waveguide published by Chen et al. . Our analysis of the orientation of 4MPy and 4ABA presumes that the local field polarization is primarily perpendicular to the nanoparticle surface. Under this assumption, modes having a substantial Raman tensor component normal to the surface will be enhanced more than those whose normal components are weak or forbidden by symmetry. Qualitatively, by comparing the SERS enhancement factor of various modes and relating these to the Raman tensors describing the unenhanced, unbound molecule, one can infer an approximate orientation -flat or upright on the surface. Underlying this approach are a number of conditions that need to be met. The requirement that the polarization is perpendicular to the surface is difficult to justify in the case of rough metal surfaces, colloidal suspensions, and most likely, nanoplasmonic particles on the OCB. Furthermore, the enhancement factor for various Raman modes must be distinguishable from other effects, notably the dispersion in the plasmon resonance, which causes the enhancement factor to depend on the Raman shift . Given these challenges, one must resort to qualitative arguments around the SER selection rules to assign molecular orientation. Hence, the arguments for the different orientations of 4MPy and 4ABA remain qualitative.