Eu@Sc_20C_60: Magnetic Volleyballene

Recently, a stable hollow Sc_20C_60 cage with T_h point group symmetry has been proposed, due to its volleyball-like shape called volleyballene. Here the structural and electronic properties for Sc_20C_60 cage with a europium atom are further studied based on density functional theory. The results give two stable low-lying Eu@Sc_20C_60 isomers, called cage-a and cage-b, respectively, which still retain the cage-like shape of Sc_20C_60 volleyballene. After a Eu atom is encaged into the Sc_20C_60 volleyballene, the HOMO–LUMO gaps decrease from 1.47 eV of the Sc_20C_60 cage to 0.46 eV of cage-a and 0.21 eV of cage-b. Due to the half-filled 4f-electron orbital states of the Eu atom, the two low-lying Eu@Sc_20C_60 isomers have net magnetic moments of 7\mu _\rm B. This study further provides the possible applications for the Sc_20C_60 volleyballene, and enriches the species of magnetic cage-like molecules, which provides more information for magnetic storage and magnetic control.