DKH-DFT calculations of the structures, energies, and electrical and magnetic properties of Fe_n (2 ≤ n ≤ 13) clusters

At the DKH2-B1B95/DZP+1d-DKH level of theory, the following quantities were calculated: bond lengths, binding energies, equilibrium dissociation energies, HOMO-LUMO energy gaps, vertical ionization potentials, second-order differences in total energies, and spin magnetic moments of small iron clusters. The findings of this study closely align with the experimental values reported in the extant literature. The spin magnetic moments of the iron cluster cations examined in this study are among the most precise values reported to date. This finding lends credibility to the predicted geometric structures of the ground state and will undoubtedly facilitate the elucidation of the long-standing controversy surrounding the electronic structures of small iron clusters. The geometric structure for Fe₇ and the symmetries for Fe₅, Fe₆, Fe₈, Fe₉, and Fe₁₂ found in this work for the ground state differ from those previously reported. The findings of this study indicate that Fe₅ and Fe₆ are the most stable clusters, while Fe₉ and Fe₁₂ are the most reactive. In order to enhance comprehension of iron cluster electronic structures, we have computed static mean dipole polarizabilities and polarizability anisotropies for the first time.