Theoretical Prediction and Experimental Evaluation of Topological Landscape and Thermodynamic Stability of a Fluorinated Zeolitic Imidazolate Framework

The prediction of topological preferences and polymorph stability remains a challenge for the design of metal-organic frameworks exhibiting a rich topological landscape, such as zeolitic imidazolate frameworks (ZIFs). Here, we have used mechanochemical screening and calorimetry to test the ability of dispersion-corrected periodic density functional theory (DFT) to accurately survey the topological landscape, as well as quantitatively evaluate polymorph stability, for a previously not synthesized ZIF composition. Theoretical calculations were used to obtain an energy ranking and evaluate energy differences for a set of hypothetical, topologically distinct structures of a fluorine-substituted ZIF. Calculations were then experimentally validated via mechanochemical screening and calorimetry, which confirmed two out of three theoretically anticipated topologies, including a fluorinated analogue of the popular ZIF-8, while revealing an excellent match between the measured and theoretically calculated energetic differences between them. The results, which speak strongly in favor of the ability of dispersion-corrected periodic DFT to predict the topological landscape of new ZIFs, also reveal the ability to use peripheral substituents on the organic linker to modify the framework thermodynamic stability.