Browsing by Author "Mathada, Gundo"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Expansion of a porous organic molecular material induced by gas pressure
    (Stellenbosch : Stellenbosch University, 2024-03) Mathada, Gundo; Barbour, Leonard James; Stellenbosch University. Faculty of Science. Dept. of Chemistry and Polymer Science.
    ENGLISH ABSTRACT: The interplay between external stimuli and the structural properties of crystalline materials holds immerse potential for the design of novel functional materials. In this study, the intriguing phenomenon of reversible elongation of an organic crystal in response to gas pressure (carbon dioxide and ethylene) was investigated. Through a comprehensive experimental approach combining series in situ crystallography, gas sorption isotherm measurements, and photomicroscopy, we elucidate the molecular-level mechanisms underlying this behaviour. The findings of this study reveal that gas molecules infiltrate the intricate 0D cavities within the crystal lattice, prompting subtle adjustments in molecular arrangement to accommodate the guest species. The molecular rearrangement (with no phase changes), manifested as an elongation of the crystallographic c axis, is observed across varying gas pressures and molecular environments. Notably, the empirical modelling of gas-induced elongation using the Sips equation provides valuable insights into the relationship between gas pressure and crystal expansion. The in-house instruments were utilized throughout this study to investigate the observed phenomena in the crystals