Open PhD or Postdoc Position

“Joint Experimental-Computational exploration of Negative Gas Adsorption in MOFs: Towards threshold sensitive mechanical actuators”

Position for 3 years (PhD) or 2 years (Postdoc)

Starting Date: Flexible

Keywords: Flexible Metal Organic Frameworks, mechanical behavior, Molecular Dynamics.

One fascinating property of many metal-organic frameworks (MOFs) is their stimulus-induced breathing, a unique feature in the field of porous adsorbents. Recently, a MOF named DUT-49 (DUT stands for Dresden University of Technology) was identified as a unique material showing an intriguing phenomenon termed “negative gas adsorption” (NGA). This could pave the way towards novel applications in micromechanics or separation. The objectives of this fundamental project are to understand the origin of this NGA at the microscopic scale and to tune chemical functionalities of DUT-49 in order to modulate this spectacular property. A joint theoretical/experimental approach will be taken where new tools will be developed to tackle this high risk/potentially high gain project. Three groups working synergistic in MOF synthesis/structure determination (DUT), experimental adsorption (MADIREL, Marseille) and experimental/theoretical characterization of MOF flexibility (ICGM, Montpellier) will be involved.

The computational effort will develop Hybrid Osmotic Monte Carlo (HOMC) approach to explore the adsorption behavior of DUT-49s for a series of gases with the objectives to predict the gas adsorption isotherms and enthalpies and besides to identify the conditions (pressure, temperature, nature of the gas) for the existence of the NGA, to determine the amplitude of the NGA in terms of gas amount expelled, pressure amplification and associated unit cell volume change of the MOF, and to gain microscopic insight into the synergistic interplay between the dynamics of the framework and the confinement of the guest molecules at the origin of the NGA. A further step will consist of predicting how the ligand changes (functionalization and length) and the metal substitution (Co, Zn,…) can affect the NGA and the resulting structural and/or energetics features of these solids. In cases where improvements can be made in terms of increasing the amplitude of the pressure amplification, the corresponding MOFs will then be further synthesized (and the adsorption behavior of these predicted solids will be characterized for confirmation.

This project is supported by an International Collaborative ANR (France)/DFG (Germany) assembling complementary groups working in MOF synthesis/structure (Dresden University of Technology/Prof. S. Kaskel), experimental adsorption (MADIREL-P.L. Llewellyn, Marseille) and molecular simulation (ICGM-G. Maurin, Montpellier) It will offer a great opportunity for the fellow to build strong collaboration with both experimental and theoretical partners.  

Potential candidate should have a background in theory for forcefield-based simulations including Grand Canonical Monte Carlo or/and Molecular Dynamics.

Contact : CVs should be sent to to Prof. G. Maurin, Institut Charles Gerhardt UMR CNRS 5253, Université Montpellier, France, email : [email protected], tel +33 4 67 14 33 07.