In this work, we investigate the adsorption of chlorinated methanes (CHxCl4-x, x = 0-4) in a representative layer-pillar metal-organic framework, the flexible MOF Ni2(ndc)2(dabco) (ndc = 2,6-naphthalene-dicarboxylate, dabco = 1,4-diazabicyclo-[2.2.2]-octane), also known as DUT-8(Ni). The guest molecules show a systematic increase of polarizability with increasing number of chlorine atoms, whereas the dipole moment exceeds 2 debye for x = 2 and 3. Our ligand field molecular mechanics simulations show that, at first, counter-intuitively, the host-guest interactions are mainly characterized by London dispersion despite the molecular dipole moments reaching magnitudes as large as water. This highlights the importance of London dispersion interactions in the description of host-guest interactions.
Bibliographical noteFunding Information:
This project was funded by Deutsche Forschungsgemeinschaft through FOR2433. Special thanks to our collaborator S. Ehrling for providing insights into experimental procedures and results. We thank ZIH Dresden for providing computational resources.
Copyright © 2020 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films