Poster Presentation Crystal36-AXAA Conference 2026

Uncovering the behaviour of a new class of Truchet-tile-like, topologically aperiodic materials. (143682)

Matthew J McKay 1 , Cameron J Kepert 1
  1. The University of Sydney, Sydney, NSW, Australia

The discovery of quasicrystals in 1982 redefined the field of crystallography, changing even the definition of a crystal. These aperiodic crystalline materials could be topologically related to Penrose tilings, which described quasicrystals well; however, a new class of topologically aperiodic materials has recently been discovered described by a different set of aperiodic tilings—Truchet tiles.1 The first of these materials, a metal-organic framework (MOF) by the name of TRUMOF-1, has been shown to incorporate a unique type of disorder responsible for an increased resistance to applied pressure2 and unique phase dynamics,3 properties that may be appealing for applications in gas storage, gas separations and data storage. This aperiodicity leads to the generation of structured diffuse scattering, as has been characterised using single crystal X-ray diffraction methods, with the precise nature of the diffuse patterns providing a fingerprint for the short-range, non-superimposing framework configurations within the structure.1

Since the discovery of TRUMOF-1, which contains the Zn4O cluster and isophthalate ligand, three new isostructural analogues have been discovered and characterised by selecting topologically similar ligands and the same secondary building unit (SBU). This includes using 2-fluoroisophthalate (TRUMOF-2), furan-2,5-dicarboxylate (TRUMOF-3) and naphthalene-2,7-dicarboxylate (TRUMOF-4) ligands respectively. This shows that the aperiodic topology can be designed into new materials to target various potential future applications. For example, TRUMOF-4 targets larger pore sizes through the use of a longer ligand, for the functional use of gas storage and separations. Further investigations will explore cooperative phenomena such as magnetic ordering, electron delocalisation and spin switching within Truchet materials, as these behaviours conventionally exist in periodic networks of interactions. Such investigations will require the strategic synthesis of entirely new frameworks in which unpaired electrons are embedded with appropriate local environments and intraframework coupling.

  1. [1] Meekel, E. G.; Schmidt, E. M.; Cameron, L. J.; Dharma, A. D.; Windsor, H. J.; Duyker, S. G.; Minelli, A.; Pope, T.; Lepore, G. O.; Slater, B.; Kepert, C. J.; Goodwin, A. L. Science 2023, 379, 357–361.
  2. [2] Meekel, E. G.; Partridge, P.; Paraoan, R. A. I.; Levinsky, J. J. B.; Slater, B.; Hobday, C. L.; Goodwin, A. L. Nature Materials 2024, 23, 1245–1251.
  3. [3] Greenbaum, G.; Doheny, P. W.; Paraoan, R. A. I.; Kholina, Y.; Michalik, S.; Cassidy, S. J.; Yeung, H. H.-M.; Goodwin, A. L. Journal of the American Chemical Society 2024, 146, 27262–27266.