Polymeric Fused-Ring Type Iron Phthalocyanine Nanosheet and Its Derivative Ribbons and Tubes

On the basis of density functional theory calculations,
we study
the electronic and magnetic properties of an iron phthalocyanine (FePc)
nanosheet (FePcNST) and its derivatives, nanoribbons (FePcNRs) and
nanotubes (FePcNTs). The GGA+U+SOC calculations reveal
that the interesting in-plane magnetic anisotropy comes from unquenched
in-plane orbital moments for FePcNST. The calculations indicate that
the most stable antiferromagnetic (AFM) ordering for FePcNRs is G-type
AFM, which is independent of the ribbon width. In addition, FePcNTs
with radii larger than 10 Å are thermodynamically and thermally
stable and can be rolled up from the FePcNST with only several millielectronvolts
energy cost. Interestingly, the most stable AFM types of FePcNTs highly
depend on the number of Fe ions (odd or even) on the circumference.
These results may shed useful light on further experimental and theoretical
studies on the organometallic nanosheet and its one-dimensional derivatives.