Disclosed herein is a way to produce a series of discrete sized slender, rigid oligoparaxylene molecules ranging from 1-5 nm in length. Molecules, based on 1-7, 9-11 paraxylene rings, have been synthesized as part of a homologous series of oligoparaxylenes (OPXs) with a view to providing a molecular tool box for the construction of nano architectures—such as spheres, cages, capsules, metal-organic frameworks (MOFs), metal-organic polyhedrons (MOPs) and covalent-organic frameworks (COFs), to name but a few—of well-defined sizes and shapes. Twisting between the planes of contiguous paraxylene rings is generated by the steric hindrance associated with the methyl groups and leads to the existence of soluble molecular gauge blocks without the need—at least in the case of the lower homologues—to introduce long aliphatic side chains onto the phenylene rings in the molecules.