title: Characterization of two-dimensional chiral self-assemblies L- and D-methionine on Au(111).
abstract: A combination of XPS, in situ RAIRS, LEED, and STM experiments together with ab initio DFT calculations were used to elucidate the self-assembly properties at the atomic level, and enabled the interpretation of the expression of surface chirality upon adsorption of both enantiomers of methionine on a clean Au(111) surface under UHV conditions. The combination of experimental results, in particular, LEED and STM data with quantum chemical calculations is shown to be a successful setup strategy for addressing this challenge. It was found that the methionine molecular self-assembly consists of the first molecule lying parallel to the gold surface and the second interacting with the first methionine through a 2D H-bond network. The interaction with the gold surface is weak. The stability of the assembly is mainly due to the presence of intermolecular H bonds, resulting in the formation of ziplike dimer rows on the Au(111) surface. The methionine molecules interact with each other via their amino acid functional groups. The assembly shows an asymmetric pattern due to a slightly different orientation of the methionine molecules with respect to the surface. Simulations of the STM image of methionine assemblies were consistent with the experimental STM image. The present study shows another example of Au(111) stabilizing a self-assembled biological layer, which is not chemically perturbed by the surface.
authors: Sorbonnes Universités, UPMC Univ Paris 06, UMR CNRS 7197, Laboratoire de Réactivité de Surface, 4 place jussieu, F-75005 Paris, France.
authors: Vincent
authors: V
authors: Humblot
authors: Frederik
authors: F
authors: Tielens
authors: Noelia B
authors: NB
authors: Luque
authors: Harout
authors: H
authors: Hampartsoumian
authors: Christophe
authors: C
authors: Méthivier
authors: Claire-Marie
authors: CM
authors: Pradier
mesh_terms: D006046:Gold / Q000737:chemistry*; D008715:Methionine / Q000138:chemical synthesis* / Q000737:chemistry; D010316:Particle Size; D011789:Quantum Theory; D013237:Stereoisomerism; D013499:Surface Properties
chemical_list: D006046:Gold; D008715:Methionine