Exploring Fundamental Chiral Molecular Self-assembly: Proline on Cu(111) Surfaces
Authors:
- Students:
- Matthew Anderson
- Andrew Cook
- Luis Hernandez
- Joseph Jorgenson
- Kendall Queen
- Cody Summerson
- Gabriela Vazquez
- Ava Wallace
- Teachers:
- Jeff Newton
- Irina Stan
- Mentors:
- Nathan P. Guisinger (Argonne National Laboratory, Center for Nanoscale Materials)
Center for Nanoscale Materials
In this study we performed the first atomic-scale exploration of molecular self-assembly of the chiral amino acid proline on Cu(111). The goal of this research was to further the knowledge and understanding about how D- and L-proline self-assemble, noting how the chirality affects their interactions. To accomplish this, homochiral samples of proline on a Cu(111) surface were individually explored. A scanning tunneling microscope was used to map the self-assembly at a clear molecular resolution. This experiment was performed in an ultrahigh vacuum to avoid interference from outside particles. By analyzing the results, it was found that both Land D-proline form molecular trimers as base units that assemble into larger hexagonal tilings. However, the orientation of these hexagonal tilings is different between the L- and D-proline, which is due to the chirality of the amino acids.