Metal–organic framework with two different types of rigid triscarboxylates: net topology and gas sorption behaviour

Abstract

A 3-dimensional (3-D) anionic metal–organic framework (MOF), (NH₂(CH₃)₂)₃[Zn₆(BTC)₄(BTB)], of an unprecedented 3,3,3,5-c net topology was prepared via the solvothermal reaction of the Zn(II) ion with two different types of rigid triscarboxylates, 1,3,5-benzenetricarboxylate (BTC³⁻) and 1,3,5-benzenetribenzoate (BTB³⁻), as 3-connected nodes, where a structurally rare Zn₂(COO)₅ cluster serves as a 5-connected secondary building unit. The MOF has a complicated 3-D channel micropore based on three different types of cage-like pores interconnected through the narrow necklike portals of a multiway channel. The MOF that had large solvent-filled pores showed gas sorption behaviour that well matched the pore dimensions and characteristics of the MOF.