Potential-selective fate of 2D chiral crystallization on an electrode surface.

Molecular resolution STM is used to study the spatial structure and chirality of adsorbed Δ4,4-dicyclopenta[2,1-b:3,4-b]-dithiophene (TTE) on an Au(111) electrode, revealing an ordered, racemate adlayer made of homogeneously mixed R- and S-TTE on the (1 × 1) substrate and patches of R- or S-only TTE on the reconstructed Au(111) at more and less positive potentials.