The formation of regular nanostructures by photolysis of azobisisobutyronit
rile (AIBN) in the solid state is investigated using atomic force microscop
y (AFM) and known crystal packing data. AFM reveals that the crystal face (
001) of AIBN yields both craters and volcanoes. All the experimental result
s are correlated with the crystal structure. Molecular interpretation of th
e AFM features of AIBN is given.