Figure 7
STM empty-state images of the Si(001) surface: a c(8 × 8) unit cell is marked by the white box in image (a) (+1.9 V, 50 pA), distances between the rows marked by 'A' and 'B' equal 3a and 4a (which correspond to c(8 × 6) and c(8 × 8) structures, respectively), two long "rectangles" and divacancies arising in the adjacent rows are marked by 'L' and 'V', respectively; a row wedging between two rows ('W') and lost blocks ('LB') are seen in (b) (+1.6 V, 100 pA).