title: Stereoselectivity and electrostatics in charge-transfer Mn- and Cs-TCNQ₄ networks on Ag(100).
abstract: Controlling supramolecular self-assembly is a fundamental step towards molecular nanofabrication, which involves a formidable reverse engineering problem. It is known that a variety of structures are efficiently obtained by assembling appropriate organic molecules and transition metal atoms on well-defined substrates. Here we show that alkali atoms bring in new functionalities compared with transition metal atoms because of the interplay of local chemical bonding and long-range forces. Using atomic-resolution microscopy and theoretical modelling, we investigate the assembly of alkali (Cs) and transition metals (Mn) co-adsorbed with 7,7,8,8-tetracyanoquinodimethane (TCNQ) molecules, forming chiral superstructures on Ag(100). Whereas Mn-TCNQ(4) domains are achiral, Cs-TCNQ(4) forms chiral islands. The specific behaviour is traced back to the different nature of the Cs- and Mn-TCNQ bonding, opening a novel route for the chiral design of supramolecular architectures. Moreover, alkali atoms provide a means to modify the adlayer electrostatic properties, which is important for the design of metal-organic interfaces.
authors: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
authors: Nasiba
authors: N
authors: Abdurakhmanova
authors: Andrea
authors: A
authors: Floris
authors: Tzu-Chun
authors: TC
authors: Tseng
authors: Alessio
authors: A
authors: Comisso
authors: Sebastian
authors: S
authors: Stepanow
authors: Alessandro
authors: A
authors: De Vita
authors: Klaus
authors: K
authors: Kern
mesh_terms: D000468:Alkalies / Q000737:chemistry*; D036103:Nanotechnology; D009570:Nitriles / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D055672:Static Electricity; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D000468:Alkalies; D009570:Nitriles; D028561:Transition Elements; C013703:tetracyanoquinodimethane; D012834:Silver