Pt(211) Surface (IMAGE) American Institute of Physics Caption The Pt(211) surface has three-atom-wide terraces and one-atom-high steps. The researchers labeled the row of atoms on the step edge as "step" (red), the middle row as "terrace" (black) and the final row as "corner" (gray). Credit Han Guo Usage Restrictions This image may be used only with appropriate credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.