Tip‐Enhanced Raman Spectroscopic Studies of the Hydrogen Bonding between Adenine and Thymine Adsorbed on Au (111)

STM tip-enhanced spectroscopy is employed to study the hydrogen bonding between adenine (A) and thymine (T) at monolayer coverage at a Au(111) surface. The AT base pair adsorbs nearly vertically at Au(111) with A close to the substrate and T exposed away (see picture). In contrast to the observation at neutral pH, no AT hydrogen bonding at pH 1 is found.