1→3 Dimensional Structures on a Uni-Directional Substrate

STM has been used to examine the morphology of a highly anisotropic substrate, TiO2(100)1×3, including the interaction of steps in the two principal azimuths. The ability of this substrate to align adsorbates so as to produce low-dimensional structures has been investigated. One dimensional arrays of segregated impurities are formed in deep troughs produced by a down step immediately followed by an up step. C60 molecules preferentially occupy sites at the top of the microfacet morphology, which contains Ti3+ species. At higher coverage, the corresponding valleys are populated, forming an epitaxial double layer of fcc C60(110).