Steric hindrance in the on-surface synthesis of diethynyl-linked anthracene polymers

TL;DR

This paper investigates how steric hindrance influences the formation of diethynyl-linked anthracene polymers on Au(111), revealing that steric effects affect polymer ordering and stability during on-surface synthesis.

Contribution

It demonstrates the impact of steric hindrance between aromatic groups on polymer formation and ordering in on-surface synthesis using anthracene precursors.

Findings

Steric hindrance affects polymer domain formation.

De-metalation causes lateral separation of polymers.

Steric effects influence the stability of organometallic structures.

Abstract

Hybrid sp-sp2 structures can be efficiently obtained on metal substrates via on-surface synthesis. The choice of both the precursor and of the substrate impacts on the effectiveness of the process and the stability of the formed structures. Here we demonstrate that using anthracene-based molecules as precursor, the formation on Au(111) of polymers hosting sp carbon chains is affected by the steric hindrance between aromatic groups. In particular, by scanning tunneling microscopy and density functional theory calculations we show that the de-metalation of organometallic structures induces a lateral separation of adjacent polymers preventing the formation of ordered domains.