[Zr6O4(OH)4(benzene-1,4-dicarboxylato)6]n: a hexagonal polymorph of UiO-66.

ABSTRACT

Since its discovery in 2008, the paradigmatic UiO-66 has behaved as the germ that has prompted the chemistry of group-4 metal based metal-organic frameworks, all of them featuring outstanding thermal and chemical stability. Herein we present the first polymorph of UiO-66 and the key conditions that led to its formation.