Fig. 11 shows you the functions available here.
Once you achieved atomic resolution, apply the Spec button. The
actual image is transferred to the spectroscopy panel. Use the Point
button to position the tip above a carbon atom. Check the rel checkbox
and select Z-Axis from the Output menu. Carefully
increase the range of the scan by adjusting the from and to
values. As you do not know the
exact distance to the surface, you have to approach an x value where
the current limitation prevents a further increase of the tunneling current.
Save three I/z-Curves for further interpretation.
![\includegraphics[width=110mm]{specpanel.eps}](img39.png)