Chiral recognition of organic molecules by atomic kinks on surfaces.
Two distinct non-mirror-symmetric conformations of D- and L-cysteine were found after adsorption on Au(17 11 9)S. This demonstrates chiral heterorecognition, i.e., enantioselectivity of S kinks on vicinal Au(111). The structures as determined by angle scanned x-ray photoelectron diffraction agree well with those from density functional theory calculations. The calculations predict adsorption energies of approximately 2 eV where D-cysteine binds 140 meV stronger than L-cysteine. The classical three point contact model for molecular recognition fails to explain these findings.
Physik Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
T
T
Greber
Z
Z
Sljivancanin
R
R
Schillinger
J
J
Wider
B
B
Hammer