CFx: A first-principles study of structural patterns arising during synthetic growth

Structural and bonding patterns arising from the incorporation of fluorine atoms in a graphene-like network relevant to the deposition of carbon fluoride (CFx) films were addressed by first-principles calculations. We find that large N-member (N = 8–12) rings, defects by sheet branching, and defects associated with bond rotation pertain to CFx. The cohesive energy gains associated with these patterns are ∼0.2–0.4 eV/at., which is similar to those for a wide range of defects in other C-based nanostructured solids. Fullerene-like CFx is predicted for F concentrations below ∼10 at.%, while CFx compounds with higher F content are predominantly amorphous or polymeric.