| AVS 66th International Symposium & Exhibition | |
| Nanometer-scale Science and Technology Division | Wednesday Sessions |
| Session NS-WeM |
| Session: | Optics and Scattering on the Nanoscale |
| Presenter: | Jeremy Schultz, University of Illinois at Chicago |
| Authors: | J. Schultz, University of Illinois at Chicago N. Jiang, University of Illinois at Chicago |
| Correspondent: | Click to Email |
Molecular self-assembly on surfaces is defined by the unique set of circumstances that arise from the complicated interplay of molecule-molecule and molecule-substrate interactions. These interactions are defined by their highly localized chemical environments. As a result, it becomes necessary to apply spatially resolved techniques. In this work we have applied two primary techniques to the study of intermolecular and molecule-substrate interactions. Scanning tunneling microscopy (STM) reveals local electronic effects and structure, while tip-enhanced Raman spectroscopy (TERS) defines the vibrational fingerprint of a molecule which is highly sensitive to localized chemical effects. In combination with gas phase Density Function Theory (DFT) calculations it is possible to define the effects of molecule-substrate interactions on the molecules’ vibrations. Three different systems involving organic molecules on single crystals have been examined: boron subpthalocyanine, 3,6-dibromo-9,10-phenanthrenequinone, and rubrene. Through the tandem technique of STM-TERS, intermolecular interactions that result in self-assembly, specifically hydrogen bonds, halogen bonds, and van der Waals interactions have been characterized. Similarly, molecule-substrate effects on molecular configuration and binding strength have been considered through comparison with DFT simulated Raman spectra to obtain a detailed description. Ultimately, the application of complementary techniques results in highly descriptive vibrational fingerprints with spatial resolution.