ZIF-8. ZIF-8 is composed of Zn 2+ ions coordinated to 2-methylimidazole ligands within the SOD topology and exhibits a BET N 2 surface area of 1080 m 2 /g . From the crystal structure, we calculated (via PoreBlazer ) the diameter of the largest hard sphere that can be included in its pores as 13.06 Å.