High-Resolution STM Studies of Terephthalic Acid Molecules on Rutile TiO2(110)-(1 x 1) Surfaces

The structure of terephthatic acid (TPA) molecules adsorbed on rutile TiO2(110)-(1 x 1) has been investigated by scanning tunneling microscopy (STM). Molecularly resolved STM images show formation of monolayer with the tendency of TPA molecules to form dimer rows along the [001] substrate direction. The ability to image functional groups by the STM tip, and single molecule diffusion are demonstrated. The quality and stability of the monolayer are tested, including the resistance against air exposure. On the basis of results obtained, the model of TPA adsorption on the rutile TiO2 (110)-(1 x 1) is proposed.