Perfect Monolayers of the BaTiO3‐Derived 2D Oxide Quasicrystals Investigated by Scanning Tunneling Microscopy and Noncontact Atomic Force Microscopy

The atomic structure of the BaTiO3‐derived 2D oxide quasicrystals (OQCs) is investigated using scanning tunneling microscopy (STM) and noncontact atomic force microscopy (nc‐AFM). It is demonstrated that these extraordinary films can easily be prepared as single‐phase monolayers on a Pt(111) support. From analyzing almost 20 000 atomic vertices, an extended statistical dataset of the OQC tiling is collected. It manifests that the OQC obeys the statistics of the Niizeki–Gähler tiling, which is a dodecagonal triangle–square–rhomb model system. The atomic structure shown by nc‐AFM is identical to the contrast obtained in STM images. The results are discussed with respect to the existing structural models. Simultaneously measured tunneling current and frequency shift image of the 2D oxide quasicrystal derived from BaTiO3 is shown here. The atomic structure revealed by noncontact atomic force microscopy is identical to the contrast obtained by scanning tunneling microscopy. The results are discussed with respect to the existing structural models.