Figure 4: (a) An STM image of 0.2 ML NO on Pt(997) at 86 K.  V,  pA, 11 nm × 5.5 nm. The registry mesh is drawn based on adsorbed NO molecules on the terrace as a reference. The intersections correspond to the position of Pt atoms. (b) A schematic drawing of the adsorption sites of the NO on Pt(997). HT (fcc and hcp), OT, BS, and HS species are energetically stable. However, an HS (hcp) site is not stable.