Data files represent STM (scanning tunnelling microscopy) measurements by Dr Renald Schaub and coworkers. STM raw data files can be opened using either 1) Createc Analysis Software, or 2) WSxM. Data files contain raw STM data (as acquired, i.e. unprocessed). For the purpose of the related publication, data were processed through a home-developed analysis software package based on Igor Pro (Wavemetrics).