Structural growth in iron oxide clusters: Rings, towers, and hollow drums

Electron impact ionisation cross sections of iron oxides

“…However, the latter was obtained for a spin-triplet configuration employing GGA exchange and correlation functionals which may give rise to this discrepancy since bond angles are usually also more sensitive to the used methodology than bond lengths. The C2v symmetry of the obtained FeO 2 ground state is, however, in accordance with the literature [31,32,61]. Concerning the Fe 2 O 2 molecule we get a regular tetragonal structure with one Fe-O bond length of 1.85Å.…”

“…Concerning the Fe 2 O 2 molecule we get a regular tetragonal structure with one Fe-O bond length of 1.85Å. Earlier investigations yield also such regular configurations with slightly smaller Fe-O bond lengths of 1.81Å [32] and 1.79Å [37]. Whereas Ju et al [37] obtained a spin-septet ground state, the lowest energy spin configuration obtained by Jones et al [32] was a spin-singlet and in our case the ground state corresponds to 2S + 1 = 9.…”

“…We used the structures obtained by Jones et al [32] for Fe x O x and Fe x O x+1 compounds with x = 1, 2, 3 as starting geometries that were further optimised employing the B3LYP [53] density functional in conjunction with the Def2-TZVP basis set [54,55]. The binding energies, E BE , of the iron oxide clusters were determined according to: (4) where E(A) denotes the energy of compound A including the zero-point vibrational energy.…”

“…Due to the unique properties of iron oxide nanoparticles and their applications [27][28][29][30], iron oxide clusters, as their building blocks, were subject to numerous theoretical studies focusing on energetic, geometrical and magnetic properties, see e.g. references [31][32][33][34][35][36][37]. While the structures reported by Jones et al [32] were used by us as input for structural optimisation (Sect.…”

“…references [31][32][33][34][35][36][37]. While the structures reported by Jones et al [32] were used by us as input for structural optimisation (Sect. 2.3), the mentioned studies allowed us also to cross-validate our results for the obtained structural parameters and the energetics (Sect.…”