On-surface visualization of the influence of the chemical environment on halogen–hydrogen bonds at submolecular scale

Abstract

The halogen–hydrogen bond has demonstrated remarkable potential in controlling molecular assembly and precisely steering reaction pathways on surfaces. However, few attempts have been devoted to explore the fundamental characteristics of halogen–hydrogen bonds in real space. Herein, we systematically investigate the influence of the local chemical environment of hydrogen atoms on halogen–hydrogen bonds. Combining high-resolution scanning tunneling microscopy investigations with density functional theory calculations, we clarify that tuning the chemical environment of hydrogen atoms varies corresponding halogen–hydrogen bonding strengths on the Ag(111) surface, leading to the formation of different two-dimensional tessellation patterns. Our studies provide real space insights into the mechanism of halogen–hydrogen bonds and establish a strategy for designing complex low-dimensional nanostructures on metal surfaces.