Visualization of a molecular dynamics run.

Once you have run Siesta on the fdf file provided, you 
will have .XV, .ANI, .MD, and .MDE files.

The 'md2axsf' program by Andrei Postnikov can use the
coordinate information in the .ANI or the .MD files, and
will produce a .AXSF file.

Run Xcrysden:

xcrysden --axsf filename.AXSF

and use the "animate" panel to watch the simulation.

NOTE: You might want to change the origin in the .fdf
file to avoid the "break" in the Si slab.