Soft porous crystals (SPCs) can undergo cooperative responsive structural transitions that strongly impact the physical properties and pore structure of the crystal. Flexible Metal-organic frameworks are currently considered the prototypical SPCs but structural transitions in other kinds of porous solids are recently reported.

Although an increasing amount of SPCs are recently reported, they are often discovered by chance. So far a coordinated rational approach towards the intended design of SPCs is missing.

We explore common features that define the softness and explore in what way the selection of the building blocks influences the resulting structural transitions.

S. Krause, V. Bon, U. Stoeck, I. Senkovska, D. M. Tobbens, D. Wallacher, S. Kaskel, A Stimuli-Responsive Zirconium Metal-Organic Framework Based on Supermolecular Design. Angew. Chem. Int. Ed. 2017, 56 (36), 10676–10680.

S. Krause, J. D. Evans, V. Bon, I. Senkovska, P. Iacomi, F. Kolbe, S. Ehrling, E. Troschke, J. Getzschmann, D. M. Többens, A. Franz, D. Wallacher, P. G. Yot, G. Maurin, E. Brunner, P. L. Llewellyn, F.-X. Coudert, S. Kaskel, Towards general network architecture design criteria for negative gas adsorption transitions in ultraporous frameworks. Nat. Commun. 2019,10 (1), 3632.

For a comprehensive overview of the field of Soft Porous Crystals read our recent review: Chemistry of Soft Porous Crystals – Structural Dynamics and Gas Adsorption Properties.

Illustration of the free energy landscape of soft porous crystals.