  The nucleation of graphene on Ni surface, as well as on the step, is studied
using a tight binding method of SCC-DFTB. The result demonstrates that the fcc
configuration has the lowest total energy and thus is the most stable one
compared to the other two structures when benzene ring is absorbed on the
Ni(111) surface. The activity of marginal growth graphene's carbon atoms
decreases from the boundary to the center, when they are absorbed on the
substrate. Graphene layer can grow continuously on step surface formed by
intersection of Ni(111) and Ni(1-11) surface. Meanwhile, a mismatch will occur
between the layer and Ni surface and thus leads to flaws when the layer grows
larger. Reducing the mismatch between the graphene and the step surface will
benefit the growth of graphene of large area and high quality.
