Helical Conformation Tunability via Hydrogen Bonding in Supramolecular Frameworks

Hydrogen-bonded molecules and their dynamics are significantly important in chemistry and biology due to their widespread functionality.Besides their natural abundance and diversity,applications of molecules with dynamic conformations in artificial networks allow information storage and molecular motor design on the nanometer scale.Here,we report hydrogen-bonded molecular networks with tunable helical conformation on metal surfaces.The dynamics of helical conformation in two-dimensional hydrogenbond networks are triggered and resolved by scanning probe microscopy at the single-molecule level.In combinationwith theoretical calculations,the surfacespecific hydrogen bonds are identified as the origin of the dynamic helical conformation.Our results provide a distinctive access to molecular architecture with tunable helical conformation driven by hydrogenbond interaction on surfaces.