Structural and magnetic properties of FeGe (n = 3-12) clusters: Mass-selected anion photoelectron spectroscopy and density functional theory calculations.

The structural, electronic, and magnetic properties of FeGe (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 = 3-12) clusters with n ≤ 7, the dominant structures are exohedral. The FeGe 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 cage from n = 9 to 11. The structures of FeGe can be viewed as two Ge atoms symmetrically capping the opening of the boat-shaped structure of FeGe, and those of FeGe 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 and local magnetic moment of the Fe atom have not been quenched.