Which atoms can be added to C60 molecules during chemical reactions?

The $C_{60}$ molecule, also known as buckminsterfullerene, is highly reactive and capable of undergoing various chemical reactions. During these processes, the molecule readily adds atoms of hydrogen and halogen elements.1

Additionally, through the formation of "endohedral" complexes, various atoms can be physically trapped inside the hollow fullerene cage. These include:

• Metals: Alkali metals, alkaline earth metals, and early lanthanoids can be encapsulated within the cage.1
• Noble Gases: Helium can be trapped inside the $C_{60}$ structure when the molecule is heated in helium vapour under pressure.1