Structures and properties of small iron-doped carbon clusters

A systemic study of the small iron-doped carbon clusters FeCn/FeCn−/FeCn+(n = 1–10) has been performed with density functional theory (DFT) method at the B3LYP/6-311+G* level. Several properties including equilibrium geometries, electronic states, relative energies, vibrational frequencies, and dipole moments have been investigated for linear, cyclic and fanlike isomers. The stability of different structures and states has been discussed according to the relative energy for the same size, and the incremental binding energy for different size. For neutral FeCn clusters, their ground states have fanlike structures for FeC2–4, linear structure for FeC5, and cyclic structures for FeC6–10; for ionic FeCn−/FeCn+ clusters, they all have linear ground states, except FeC7−, FeC9−, FeC2+, and FeC10+.