Naphtho[2,3-a]pyrene forms chiral domains on Au111

Chiral domains have been prepared by evaporation of a two-dimensionally chiral molecule, naphtho2,3-a]pyrene (NP), onto the hexagonal Au(111) surface in an ultrahigh vacuum environment. High-resolution UHV scanning tunneling microscopy (STM) showed that NP formed chiral domains consisting of only one 2D enantiomer rather than racemic two-dimensional unit cells. A structural model is proposed that agrees with the STM observations. Chiral pockets between adsorbed molecules may be useful for binding a specific enantiomer of a 3D chiral molecule.