An unprecedented twofold interpenetrated layered metal–organic framework with a two-dimensional 3,6-connected net topology has been prepared using a tricarboxylic acid as a 3-connected node and a Zn4O(COO)6 cluster as a 6-connected node, where the ligand flexibility and the combination of π–π stacking and hydrogen bonding interactions render the 6-connected node into a topological trigonal prismatic node.
