Interplay between step anisotropy and surface phase transformation on TiO2(110) - art. no. 121401

The dynamic behavior of steps on the TiO2 (110) surface was studied during the transformation from a 1 X 1 structure to a 1 X 2 structure. We found th at two types of steps dominate the transformation process: (1) [001], defin ed as steps that run along the [001] direction; and (2) [1 (1) over bar0] d efined as steps that run parallel to the [1 (1) over bar0] direction. The s toichiometric 1 x 1 surface contained mostly [001] steps. Reducing this sur face caused nearly half the [001] steps to be gradually converted to [1 (1) over bar0] steps. This evolution in step structure was accompanied by grow th of reconstructed 1 X 2 domains initiated mostly at the [1 (1) over bar0] step edges. On the 1 X 2 domains, the lengths of the [001] and [1 (1) over bar0] steps were approximately equal. The results of this work shed light on the step structure and correlation between the step energetics and the s urface phase transformations on the TiO2 (110) surface.