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

Solvothermal syntheses afforded two new MOFs {[Zn-2(L-1)(btmbb)(H2O)(4)]center dot 2H(2)O}(n) (1) and [Zn-2(L-1)(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.