Figure 3.

Simultaneously recorded (a) ES and (d) FS images of TiO₂(110) containing two single OH_bs. The images were recorded at 7 K. (b,e) As (a,d) recorded after the capping H of the OH_b on the left was removed by a +3.5 V, 1 ms tip pulse. (c,f) As (b,e) recorded after removal of the capping H of the OH_b on the right. Circles mark the OH_b positions. Image size: (2.74 nm)². Scan parameters (V, I): (a–c) +2 V, 30 pA; (d–f) −2 V, 1 pA. (g–h) Difference images formed by subtraction of the FS image in (d) from that in (e), and of the FS image in (e) from that in (f), respectively.