Structural and magnetic properties of FeGen−/0 (n = 3-12) clusters: Mass-selected anion photoelectron spectroscopy and density functional theory calculations

Abstract

The structural, electronic, and magnetic properties of FeGe_n^-/0 (n = 3-12) clusters were investigated by using anion photoelectron spectroscopy in combination with density functional theory calculations. For both anionic and neutral FeGe_n (n = 3-12) clusters with n ≤ 7, the dominant structures are exohedral. The FeGe₈^-/0 clusters have half-encapsulated boat-shaped structures, and the opening of the boat-shaped structure is gradually covered by the additional Ge atoms to form Ge_n cage from n = 9 to 11. The structures of FeGe₁₀^-/0 can be viewed as two Ge atoms symmetrically capping the opening of the boat-shaped structure of FeGe₈, and those of FeGe₁₂^-/0 are distorted hexagonal prisms with the Fe atom at the center. Natural population analysis shows that there is an electron transfer from the Ge atoms to the Fe atom at n = 8-12. The total magnetic moment of FeGe_n^-/0 and local magnetic moment of the Fe atom have not been quenched.