Homochiral Recognition among Organic Molecules on Copper(110)

Abstract

The adsorption of a prochiral quinacridone derivative (QA16C) with two alkyl chains of 16 carbon atoms on a Cu(110) surface was investigated with variable-temperature scanning tunneling microscopy. QA16C molecules prefer to assemble at 150 K into short homochiral molecular lines with two enantiomorphous orientations in which the lateral alkyl chains exhibit partial disorder. With increasing sample temperatures, the QA16C lines form larger well-ordered homochiral domains. As a reason for the homochiral recognition, we identify a rigid alignment of the molecule due to the interaction with the substrate. In addition, lateral intermolecular interactions in the form of hydrogen bonding and van der Waals interactions are identified.