Adsorption of Terarylenes on Ag(111) and NaCl(001)/Ag(111): A Scanning Tunneling Microscopy and Density Functional Theory Study

Abstract

Photoswitching materials are building blocks of next generation optoelectronic devices which may require molecule deposition on a solid substrate. However, molecule properties change upon adsorption due to surface-molecule interactions and symmetry considerations. Scanning tunneling microscopy (STM) and density functional theory (DFT) offer techniques to address interactions of functional molecules down to the single-molecular level on solid substrates. In this paper, we present a combined STM and DFT study of a tert-butyl functionalized terarylene molecule on Ag(111) and NaCl(001)/Ag(111) at ∼5 K. tert-Butyl groups aided in identifying three conformations of the compound upon adsorption on the surface. DFT calculations showed that two of these conformations refer to different adsorption geometries of the trans conformation in the gas phase. The other was assigned to the nonreactive cis conformation. For the first time, this conformation was isolated and imaged at the single-molecular level. Calculations ...