Controlling interpenetration in metal–organic frameworks by tuning the conformations of flexible bis(triazole) ligands

Abstract

Solvothermal syntheses afforded two new MOFs {[Zn₂(L₁)(btmbb)(H₂O)₄]·2H₂O}_n (1) and [Zn₂(L₁)(btmbb)₂]_n (2) [5,5′-(1,4-phenylenebis(methylene))bis(oxy)diisophthalic acid (H₄L₁), and 4,4′-bis((1H-1,2,4-triazol-1-yl)methyl)biphenyl (btmbb)]. Single crystal X-ray analyses reveal that compound 1 shows an example of a 2D non-interpenetrating network, while compound 2 is a 2D polythreading interpenetrating structure, in which two layered networks interpenetrate in a (2D/2D) parallel fashion. The different conformation of the flexible ligand might be the main factor resulting in these non-interpenetrated/interpenetrated structures. The powder X-ray diffraction, thermal stabilities, and the photoluminescence of 1–2 have also been investigated.