The paper reports computations for Mg@C-74, Ca@C-74, Sr@C-74 and Ba@C-74 based on encapsulation into the IPR (isolated pentagon rule) C-74 cage, and for Al@C-82, Sc@C-82, Y@C-82 and La@C-82 with encapsulation into the C-2v IPR C-82 cage. Their production yields are estimated using the encapsulation Gibbs-energy terms and saturated metal pressures.
The results can be related to the ionization potentials of the free metal atoms.