Modelling adsorption in fluorinated TKL MOFs

Abstract

Ligand functionalisation resulting in unprecedented enhanced adsorption in a series of structurally similar, fluorinated metal-organic frameworks is studied using molecular computations and simulations. Strikingly anomalous experimental trends in the adsorption characteristics of the TKL FMOFs are investigated and understood here using classical and quantum chemical methods. Almost identical adsorption sites and energies for all the MOFs considered herein were observed. However, experimental isosteric heats and uptake amounts between these solids have been reported to be significantly different. Therefore, ab initio molecular dynamics simulations are performed to account for the drastic effects that flexible linkers can have on gas adsorption energetics, something that low-temperature crystallographic measurements cannot completely capture.

Keywords:

• Density functional theory
• metal-organic frameworks
• isosteric heat of adsorption
• molecular dynamics

Acknowledgements

We thank DST for support. The first author acknowledges JNCASR for a research fellowship. The second author acknowledges CSIR for a research fellowship.

Supplementary data

Supplemental data for this article can be accessed here. [http://dx.doi.org/10.1080/08927022.2016.1250266]