# On-surface Assembly of Au-Dicyanoanthracene Coordination Structures on Au(111)

## TL;DR

This study investigates the self-assembly and electronic properties of Au-DCA metal-organic structures on Au(111) surfaces using STM and STS, revealing complex lattice arrangements and delocalized electronic states relevant for topological phases.

## Contribution

It reports the formation of ordered Au-DCA networks with honeycomb and kagome lattices and characterizes their electronic states, advancing understanding of on-surface metal-organic coordination structures.

## Key findings

- Coexistence of DCA islands and Au-DCA coordination structures.
- Formation of DCA₃Au₂ honeycomb-kagome lattice networks.
- Detection of delocalized electronic states involving gold and DCA orbitals.

## Abstract

On-surface metal-organic coordination provides a promising way for synthesizing different two-dimensional lattice structures that have been predicted to possess exotic electronic properties. Using scanning tunneling microscopy (STM) and spectroscopy (STS), we studied the supramolecular self-assembly of 9,10-dicyanoanthracene (DCA) molecules on the Au(111) surface. Close-packed islands of DCA molecules and Au-DCA metal-organic coordination structures coexist on the Au(111) surface. Ordered DCA$_{3}$Au$_{2}$ metal-organic networks have a structure combining a honeycomb lattice of Au atoms with a kagome lattice of DCA molecules. Low-temperature STS experiments demonstrate the presence of a delocalized electronic state containing contributions from both the gold atom states and the lowest unoccupied molecular orbital of the DCA molecules. These findings are important for the future search of topological phases in metal-organic networks combining honeycomb and kagome lattices with strong spin-orbit coupling in heavy metal atoms.